This does sound a really hard situation for you. You haven’t got anything wrong and you’re doing your best for him as you always have, so stay strong and have faith in yourself.
I would just suggest trying to look at things from his point of view (I’m sure you are). He had abuse and trauma in his early years, and then later when he probably felt safe with a new parent figure, he experienced rejection instead. He’s hurting and has a lot to process, and is at a difficult age on top of that. So my thought would be rather than feeling you have to control things (he’s obviously pushing back against that, maybe because he feels no control over much else in his life?) just let him know you’re there for him and you know he’s hurting.
I’m reading ‘The book you wish your parents had read (and your children will be glad you did)’ and can really recommend it. It has some very insightful stuff on supporting difficult behaviours, and generally just being kind to yourself. Take care and best wishes.
