If he wants nothing to do with you son, he needs to have nothing to do with your son, including discipline. He can discipline his own son, if he wants to discipline somebody. But, it sounds like he has different rules for his son, which I would not be okay with.

Well I hear a lot of excuses for your son's behavior. I'm sure your husband is tired of hearing these same excuses. I bet one million dollars your husband doesn't hate your son. He hates that you don't parent him.

I dont know if those types of lies are normal at his age...that sounds more like an early elementary type lie to me that probably should have been taken care of a long time ago. Idk, mine isnt that old yet but I cant remember lying about things like showering at 13. My first impression is he is too old for that so maybe your husband feels the same. And honestly he might be grossed out by the lack of hygiene, I would be.

So let's see - if your son is ONE MINUTE late coming downstairs he's in trouble? He's not allowed to talk to kids on his way back from school and he naturally does stop and talk to friends and then (naturally) lies about it because either way he's going to get in trouble. If he had an issue that he was always in trouble and hanging around awful kids, I'd get it the no talking to other kids, but it doesn't sound like it's the case. Frankly, that sounds awful. 

Lying about showering is a little gross and frankly unneccessary. But whatever...my son will do gross boy things too and lie about it because he's knows it's a gross boy thing. I don't think it's the end of the world. It's not great though. 

The real issue here - as I see it - is that you've not been able to enforce decent boundaries about parenting your kid. Either you have allowed someone to set the boundaries (which sound harsh and might have worked at a younger age but your son at 13 is now chafing against) or you failed to set your own boundaries. My son is only 11 and he comes back from school on his own and his ony rule is that he has to let me know if he does a big diversion or goes to someone's house. I WANT my son to hang with his friends for a few minutes before and after school. 

My advice is therapy. For you. I do not know if you had therapy after your abusive relationship, but it can help you learn to set appropriate boundaries again in your own relationship and as a parent.  When you have been so broken down it is easy to hand control to someone who seems to have your best interests at heart, but the fundamental thing here is that your husband is not parenting according to your values and that puts you in conflict. Why he's being so tough on your son is hard to know - do you feel you can ask him? Some guys think that's the way you behave with boy children - to toughen them up and teach them discipline. Some guys feel conflicted that they're investing more time and resources into the support of a kid who isn't theirs and they don't have the chance to do for their own kids in the same way. My SO is an awesome stepdad, but I see him struggling with this sometimes. I think I'm a pretty good stepmom but sometimes I worry that I do too much for his at the expense of my son. Both of us try really hard to never take this out on any of the kids. 

If you think therapy is too expensive then try divorce, that's pretty expensive. So is having a teenager who goes off the rail because they've been pressured too far or live in a hostile environment most of the time. Ask any stepmom who lives with a hostile stepkid if that's any fun? 

To me a white lie, is if I ask DH, do these pants make me look fat, and he says no you look great, but i would rather you wear a dress.   

These are not white lies, and you need to deal with that now.  But you also need to tell DH, YOU will handle your kid, unless it raises to a level that is destructive or impacts him direclty. 

.... of what white lies turn into at the ages of 26 and 29.  It's not pretty. My SD's lie all the time to their dad and treat him awful. From what I am gathering, My husband has not held them accountable for those lies - ever.  Then I come into the picture and lying is my worst pet peeve and put their feet to the fire.  I have never seen something done so consistantly and skillfully as what I have seen in the girls.  Sometimes, I don't even understand why they are lying because there is no reason to.  The youngest one tells lies so well I think she really believes them.  I just look at her like are you really that niave or what are you doing?  For example, did you all know that if a car sits in a driveway long enough on a warm day it makes noises as if it been running?  The vehicle even drops AC water on the cement when warm enough?!!!!  It would have had nothing to do with the fact that she,  18 at the time, had no liscense and took her sisters' vehicle for a little spin! Or, my other favorite one: There is one dog/male in the house who I found out the hard way was not potty trained.  I had two, TWO, baby gates put up(to limit where the dog could go) that can only be opened by a human yet I find pee all down our bedroom door and the puddle I stepped in when I discover it.  She had no idea how that got there. NO IDEA.  Even though she was the only one home at the time with the dog that she takes everywhere.......Hmmm.  I caught her twice before this incident bringing him up and over the gate when she thought no one was home.  But, I am now the bad evil one because I have held them accountable.  Not a pleasant road to be on and I am at my witts end.    They just like to play victim and make everyone else look bad.  My nieces at the ages of 7 and 10 are more mature.  This is just the tip of the ice berg if something isn't done about the lying.  They still lie at 26 and 29 but I won't frustrate you with all the stories

I think you are brave to share this with us and take the "helpful hints" shared here.  You are not a bad person but as a parent you may need to get "tough" on the lying issue.

Wish you well!