Having lived in a toxic environment with a man who stuck his head in the sand 

1. You can't go on living this way, it will slowly keep sucking the life out of you.

2. You are going to have to he the one to take action. Meaning either you go back to work and buy your DH out of the house. You decide to sell it and get seperate places. He buys you out and you get your own place 

You can continue to have a relationship with your DH but living apart. You will be a much happier and healthier person. 

Resell the house now while the market is still hot and either rent somewhere or buy yourself another home. Yes, you'll take a financial hit, but you can recover. You can't recover if you're dead or dying in the hospital.

In my opinion, if you can't get past the honeymoon without needing marriage counseling, it's not a relationship that can succeed.  Start doing what needs to be done to get prepared to leave financially, and disengage from parenting. Aside from protecting yourself and your pets/home, don't set limits or parent your SS, let your H handle it. 

For me, in your shoes right now, I would present my husband with a couple of boarding school options. There are places like Cal Farley's ranch that has minimal costs to parents or Fork Union Military Academy that has financial aid to help with the cost. If BM has given up and he is causing this much distress he needs to go be with professionals to get his life on track. 

If your husband won't agree to that then he can agree to separate. 

You aren't trapped even if it feels like it. You have the power to make changes. 
Yes- a mortgage sucks but the market is KILLER right now. Even if you just bought the home you can sell it and probably even make a little but of $. 

You can also leave, have your husband buy you out of the home- he probably won't be able to afford it. There are choices to be made and none of them include continuing the path you are currently on. 

That SS must be in a boarding school, or he must move out with SS.  If BM and BF created non functional kid not your problem.  Just tell the school or anyone other who calls.  Here is BF cell number call him. He is the parent 

I feel like I'm almost reading my story in your words. I had met my DH's then 14 year old son once when we were dating.  My DH had told me that his son, who lived with his mother, had some behavioural problems (ADHD, Oppositional Defiant Disorder), troubles at school (was expelled twice), and had "ghosted" himself for a week (didn't come home from school one day, no phone calls, no social media, police called, search put on) and returned home to his mother's like nothing happened.  There were no reprecussions for this.  He was not made to be accountable.  Mom (and my DH) were just glad he was home.

Fast forward a year later, my DH moved (before we married) in with me.  And within less than 3 months, my SS's BM kicked him out of the house and sent him to live with my DH and I.  Not much of a discussion was had between my DH and I.  His son moved in with us when he had just turned 15. 

As I said, I knew he had some behavioural issues but I was not prepared for 2 years of pure hell.  It became quite clear right away that my SS had a drug dependency and not just weed, but pills as well.  He was extremely volatile, manipulative, and basically took over our home.  It also became clear that this kid had never had any rules, boundaries or expectations set on him in his life.  He also never experienced reprecussions or held accountable for any wrong doings that he had ever done.  BM always made excuses for him and would try to get me to feel sorry for him.  She also had doctors prescribe him all sorts of medications such as Ritalin, Seroquil, Valium, Klonopin to name a few.  None of which seemed to work and he also stopped taking them and would sell them. 

We had to get a lock on our bedroom door (he stole from us and others and blatantly so).  We allowed him, once, to have a friend over and they trashed his room - for fun.  He lost that privilege.  He would go to school and not come home until the next day.  He stopped going to school.  We put him in an alternative school, but he didn't do well there either.  He began to sell drugs.  He would walk right by me in the house and go in to our garage and smoke drugs. He f'you'd me on a regular basis. 

To prefice:  I worked remotely from home so was the one who had to deal with him the most (get him up and out the door for school), I am 5'2 and my SS is 6'3 and at the time 250 lbs.

When he didn't get what he wanted, he would fly into a fit of rage to the likes I had never witnessed from anyone before.  It was scary.  He would also threaten to physically hurt my DH and I when we would shut off the wifi or change the password in the house so that he couldn't contact his druggie friends to make his drug deals.

During this time, BM did not contact him.  No calls, no texts.  She didn't even contact him on his birthday.  But she would be sure to deliver his medications. She is of the mind that a pill will fix everything.

When he turned 17, he had stopped going to school and he refused to go.  I would even drive him to school, but he would go in and once I drove away, leave. He wouldn't listen to me, his dad, the prinicipal, anyone.  But he couldn't be in the house if he didn't go to school because I had to work and he was too distructive and I was uncomfortable with just he and I in the house. I had had enough.  I couldn't do it anymore and thankfully my DH backed me up.  It was time to send him to rehab.  It was our last resort.  He didn't want to go, but didn't have a choice (he was still a minor).  We consulted BM, she approved but didn't bother doing any of the work to find and get him in to rehab.  That fell on me.  He finally went but got kicked out 2 weeks later for fighting.  His dad and I went to pick him up and took him to the hospital to get assessed.  He was so good at manipulation, that he was able fool the doctor who in turn made us (not me, my husband) feel guilty for even bringing him there.  He came home with us but we laid down ground rules with no negotiations.  One misstep and he was out.  

Less than 24 hours later he was up to his old tricks, hacked the wifi (we had changed the password) and waited for a friend to stop by to "drop off something" for him.  I asked him what.  He said drugs.  He wasn't even scared or worried - he just disrespectfully said it like it is to me.  I calmly told him, to get out.  He got in my face and screamed, turned around and went to his mom's.  I called my DH to let him know what happended and he agreed.  BM called shortly afterwards stating that our "rules" were too stringent (I'm sorry, I don't want a drug dealer living in my home) and that she would come to pick up his belongings.  She arrived with him.  He stormed out of the car and got within an inch of my face yelling at me with the cords in his neck popping out and his eyes bulging.  And BM just told him to stop it.  I don't know how I was able to stay calm but somehow I did and told him that if he didn't leave I would call the police have him charged with trespassing.

I let my DH know what had occured and that his son from that day forward would never live or sleep under the same roof as me. Ever.  

That was 4 years ago.  And that boundary has stuck.  He also has learned to not call us for money or to bail him out if he gets in trouble with dealers or goes to jail.  His life, his choices. And he still chooses that lifestyle.  He was arrested a year ago for a rage attack he had at his girlfriend's place and was admitted to a psych ward of a hospital for 2 weeks where he was diagnosed with anti social personality disorder (sociopath spectrum).  This diagnosis explained so much.  But also means he will have a very tough go in life because of it.

As hard as it can be do, I disengaged from him a few years ago.  Not my kid even though he was literally thrown on my doorstep and I had to step in as one of his caretakers.  He was never my responsibility to manage or to take care of.  I did the best that I could given the circumstances and made some mistakes along the way of course - what parent hasn't.  But at some point, enough is enough.  My health and safety were at risk and that was the final straw. 

To this day I am his scapegoat.  But I don't let it affect me any longer.  My husband has thankfully had my back during all of this and still does when my SS has his "episodes".

The name of the game is disengage.  Don't enable.  Set clear and sustainable boundaries and stick to them. Communicate with your partner to be sure you are both on the same page or at least that your partner will have your back.  And if possible, get therapy for your SS now while he is still young (and possibly for you and your partner as well).  And if all else fails, and your partner is unable to back you or be on the same page, know that you have done everything in your power to make things work. But for the good of your health and possible safety, walk away. It's a tough situation to be in that is for sure but know that you are not alone.  I wish you well.

And was a stay at hone housewife while we had our 2 young kids. I was the one maintaining our marital home whilst hubby was at work and I certainly wasn't gonna continue having disrespectful lazy arse adult ss in our home.

a marriage is a partnership and if both of you contributed to the mortgage, he doesn't get to make executive decisions because he's supposed to respect you in a partnership. Same thing if you are the stay at home housewife keeping the home maintained. 

big life decisions need to be discussed with you or it breeds resentment