Does your OH has children himself? It is a bit similar in my household. OH dotted on my two and so did they until they turned the not so pleasant stage of pre-teenage years.
I handled it by disciplining them to an extent but also accepting that it IS a stage, one they all go through, they will get over with, and if I were to only focus on the negatives, my relationship with my children would suffer. OH doesn't have children and struggle to understand this. He thinks I should constantly be at the back of my DS to make sure that his bedroom is always tidy. He believes that I am not strict enough and that if I took his phone, all privileges away, punish him etc... he would finally get it. My point is that although I do not like the state of his room, taking the above extreme approach would mean that he would not want to have anything to do with me and as a result, would lose our good relationship. I don't ignore the problem, I nag and nag and nag, sometimes really get angry with him but I also accept that it is very much part of him being a teenager.
The relationship between him and DD went through the stage where he felt quite negative towards her, until she got over that awkward phase, and now they get along great. Now it's the turn of DS but more severe. Thankfully, they just ignore each other and I am confident that when DS also gets over that stage, they will rebuild their relationship again, although I expect it will take longer than it did with DD.
OH says that DS shows attitude towards him. I try to explain to him that this is because he is always so negative towards him. The only communication he has with him is to pick him up on things he doesn't do, never anything positive. I think he knows that, but is struggling to 'like' him at the moment. I have noticed that going on our annual holiday always help as they have no choice but to spend more time together and communicate. The moment OH will start being a bit more positive, DS will be more engaged and pleasant. I am confident it will come though, just have to be patient.
I remember my parents going on and on about how my sister and I were really not great company when we were teenagers and I didn't really see what they were about until I face it myself! It's hard enough as a parent, let alone as a step-parent.