I need some help on these types of indiscretions

To start my husband and I have been married for 8 years now. He has a serious problem that I’ve dealt with many times. To get to the point my husband goes online to forums like Reddit and makes post about us being swingers and how I like to watch him with other woman. He constantly talks to other couples about how we would like to join them and how I love to watch him. He posts pictures of me (without my permission) and talks about how he wants them and a lot of vulgar things like that. I am NOT okay with that lifestyle for us, I’ve made it clear since the beginning so I don’t know where this obsession came from. When I catch him I always ask the same thing, why do you do it? He says it’s because he has a problem and he can’t control that side of him. I ask him if he really wants me to sleep with other people and he tells me no but seeing what I see tells me a different story. I love my husband and he said he would go to therapy. And honestly I’m going too, he’s put me through so much I don’t know how to deal with it anymore and I fear I’m just getting used to being treated like that. Please no bashing or rude comments, I don’t have anyone to talk to about this and I feel stupid coming on here and getting help/advice from strangers.

I’ve you’ve made it this far, thank you for reading.