Your BM hates DH more then she loves SS. That situation is just horrible, been there done that. Unfortunately, there is not much you can do. Save the email - especially where she told SS daddy doesn't want to talk to you. Start the documentation trail. 

I don't really think that any change in contact methods will help. Maybe change his notification settings. However, he should only respond to TRUE emergencies immediately. Dh nees to train BM that he will address things at his convienence. 

"Dear BM,

I see that we have several issues that need to be discussed and resolved in an updated court order. I'd also like to make changes to our current call schedule and include at least three calls per week at a specifies time that is conducive to both our schedules. Additionally, I'd like to revisit parenting time and add a Wednesday visitation every week, as is standard here in our state/province/country. Let's set up a time with a mediator to discuss these changes and come to a mutually beneficial agreement. If we cannot, then I am prepared to take this to court to allow a neutral third party provide us with some clarification on the situation in our CO.

Please let me know by Friday if you'd prefer to use a mediator or involve the family court. If you'd prefer the latter, all future communication will come through my attorney."

Fight BS with fire. She thinks your BF is scared. Call her bluff. Let her show her absolute crazy, in writing.

This is what's called an "extinction burst". When you try to change a behavior, it gets WORSE before it gets better. If your BF ever wants to have a life free from BM's interference, he's got to deal with his fear and face this head on.  She will keep trying new and different things for a bit, and then the behavior will fade. But yes, it might mean she takes him to mediation or to court. He's risking losing time with SS (though hopefully not, if he hasn't done anything wrong).  But the alternative is to allow this woman to control his life and his time,  until the child is 18.

Just ignore all of this. All of it. If she really wanted SS5 to skype DH, she would have hit the button and put his little face in front of the screen. It's all just manipulation.

And yes, she is showing that she doesn't care about SS really, he's just a tool and a weapon.  Get used to it.  This is how these women operate.

Yes, it can get worse before it gets better but once she knows that he will stand his ground and that he is not afraid of her, she will eventually stop with the threats. Sometimes, you have to play their own game.

When my DH took BM to court for contempt, she realized that she was not the only one who could take someone to court. She NEVER expected him to take her to court (and he got what he wanted). She just thought she could do whatever she wanted and he would let her. We refused to live that way. It didn't stop her from being a complete bitch at pick ups and drop offs, but she knew she couldn't threaten him with court, anymore.

BM over here would tell DH the wrong meeting place, then tell SD that he didn't love her and didn't want to see her, so I know what you are dealing with, there, too.

Your BF has to stay strong and not let her use the kid to manipulate him or she.will.never.stop.

I've been there and it does suck (been with DH since SD28 was 5). The manipulation never completely stopped until SD got married at 18 and CS stopped, but it was a lot more subtle (she gave up on the threats) and less often. After CS stopped, DH refused to have ANY contact with BM.

Did I miss something, or am I the only one sitting here wondering why a child is losing a tooth at 5-years-old?

"He said that this would all end if we just give her what she wants..."

Unfortunately this is the exact opposite of what would happen.

Three things,

(1) It sounds like there are some type of court orders in place but its unclear what kind. If BF does not already have a legal parenting plan and child support agreement signed by a judge, GET ONE. Even if it means serving BM court papers. Until he has one, BM can hang whatever she wants over his head and he has no legal recourse if and when it gets bad.

(2) Neither you nor BF can control what BM does and no amount of "letting her have her way" will help turn a dysfunctional BM situation into a working one. More dangerously, by giving in to her, your BF is handing over what little negotiating power he has, and allowing her to set the rules in both HER and HIS household.  Imagine years of her chipping away one thing at a time, and BF handing it over in the hope that soon she'll be happy and collaborative... he will not have much at all in the end - which is exactly where my BF found himself after 3 years of "just this one more thing to keep the peace." However, what you CAN do is control how you jointly react to it and your BF CAN (and needs to) set and enforce both personal and legal boundaries.  It sounds like hes trying to establish boundaries for appropriate interactions - now he needs to stay firm in them and within the bounds of the parenting agreements.  For a time, BM will kick, scream, cry and tantrum like a child when this happens - she will try to bulldoze those boundaries by any means possible.  She may retaliate (withholding information or exchanges with the child), find compelling excuses to violate the boundaries (exaggerating or contriving "emergency" situations), or may even pretend to be nice and friendly for a while hoping that BF will soften and relax the lines.  I dealt with a BM who liked to rotate among all three randomly.  When she does this - as long as she is not blatantly violating the parenting plan with enough evidence that you can document to show to the court (more on that below), BF (and you) must ignore her.  Do not respond - if she texts, do not text back; if she calls, dont answer; if she takes the Skype from her kid in the middle of a session, ask for the kid to be put back on and if she refuses, hang up; if she shows up in person, walk away; if she starts talking while exchanging the kid, say "I dont want to talk about it now" or more bluntly "please email me about this" and ignore all other things she says during the exchange.  ONLY respond to the types of interactions that meet the boundaries you have put in place.  If you have said she must email, ONLY respond to email. If she sends nasty emails, ONLY respond to emails, or content within the emails that you must respond to for logistical child pickups or other appropriate topics.  IF she retaliates by violating any court orders or parenting plan agreements - use the legal process to enforce them - that's exactly what they're for!  She CANNOT simply remove or reduce BFs time with his kid because shes angry - unless abusive situations exist and can be proven, the court will not suddenly take away time from one parent and give it to another after a plan is already in place. Most judges actually look out for this type of retaliatory behavior and it may go poorly for her if she attempts this (coming from someone in a very liberal, BM centric state... it still does not end well for her if she tries this).  Still, if she starts doing this, read the parenting plan, read articles about what is and is not required by the courts in this situation. BF needs to know and 100% adhere to his responsibilities, and keep a running list with each and every time BM violates one of her responsibilities. Make sure this list includes the day, time, what the parenting plan or court order said should have happened, what actually did happen, and what evidence you have to support it (texts, emails, witness, etc.).  If she does this enough, take her to court with this list and your evidence to enforce a court order.  BF can ask for more time or other adjustments in this case if the judge agrees that she is in contempt of the parenting plan.  But hopefully it doesnt get there.  Just remember, no amount of "letting her have what she wants" avoids ending up in this spot - if it was going to go here, it'll get here either way, BF will just have far less to negotiate with if he has already been handing her all of his bargaining chips and letting her rule his roost this whole time.

(3) This is for you, specifically. It is your BFs role to establish and enforce these boundaries. While you can support him in how difficult and miserable this situation is, YOU cannot establish a boundary for the BM that your BF does not enforce 100% of the time and have it still work. If your BF is willing to put these boundaries in place, that is wonderful, and things will get slowly better over time as BM first tantrums (which is awful and annoying) but then simmers out as she realizes that she has a box of control called her own damn home, and that control does not extend to you, your BF, or violating parental plans or court orders - which largely includes withholding the child from communicating with his father.  If your BF is not willing to establish or enforce, or just half-heartedly enforces boundaries and lets BM "break the rules" from time to time... then BM will learn that as long as she continues to tantrum and raise all hell, BF will do what she wants. It will never end. She will not wake up one day and think, "gee, hes given in alot over the years, maybe I dont want to make demands anymore." Its just not going to happen - she's found a venue to get what she wants, and unless your BF is ready to cut that off completely with no exceptions, she will keep pulling those strings. And for you... you'll have to watch the whole circus of mistakes over and over as your BF (and you) get frustrated with her antics, he gives in, she continues to want more, and life begins to revolve around her and what she wants.  Over time you'll feel her presence in every interaction and every house rule you have, even though shes not even there.

So yeah (1) Legal documents, (2) Establish & ENFORCE boundaries, (3) Know who has the power to do this, who doesn't, and what happens in each case.

1.  Alienation will ACCELERATE if BF gives in

2. Being scared of BM will cause her to increase her boldness/outrageous demands

3.  An HCGUBM's twisted mind is always at work trying to hatch "payback" schemes....using the child(ren) as weapons against dad who had the AUDACITY to move on.

Raeisa gave perfect advise so I just want to add a couple of things.

Depending on how your homes are, SS is probably old enough to walk from the car to the door and back without anyone holding his hand.  That means the travelling parent should stay in their car and the other parent should stay in their house.  If your BM is as cray as Satan is, you may have to ask the court for a no contact order, like we did.  She's not allowed to any face to face contact with DH.  That also means she is not allowed to approach him in public.  If your BM cannot behave, make her.  

In the meantime, and even after a no contact order, DH should set his phone to video record her anytime she is in proximity, and point the phone right at her.  If she does approach, he will have everything documented.  Most likely she will run away with her tail between her legs.

These women are black holes of need.  They always want more.  They are never full.  You have to take your life back or suffer under their chaos for years.  This is a hill to die on.

It took a long time to train Satan, but she doesn't bother us anymore.  DH answered ONE text from her a couple years ago after years of silence and she went nuts and texted him 30 more times in the next couple of hours.  Big mistake.  She's like a flood of sewage pressing up against a dam.