Worried I have too much hope for (ex)partner's recovery and our future

Well, I didn't think I'd be here at all. I found out this past weekend that my (29f) boyfriend (30m) of a year and a half has been lying to me about not watching porn and covering up a whole addiction for the entirety of our relationship. I remember learning that he watched it when we started dating, and after I expressed concern over it at all, he told me he stopped. A couple of times after that, I asked him how it was not watching anything, and he said it was going well. I initially thought it was more casual viewing, so I took him at his word.

Throughout our relationship, we had issues around intimacy. He always ravished my body and eagerly took care of my needs, but when it came time to do the deed, he never could quite get there. He blamed it on his own self-esteem issues and feeling overwhelmed in the moment. I didn't want to pressure him, especially because he's never gone that far, but it was rough. I encouraged him to go to therapy for it, and he did start seeing a sex therapist, but only intermittently. He would say his sessions went well and how he wished he started sooner but then wouldn't go again for weeks.

Last weekend, we went to a couple's session with his therapist. Long story short, he ended up confessing to lying to me about his porn use and admitting to the addiction that's been around way before me (10ish years). I was devastated. I felt so betrayed, and my trust was broken. The next day, we talked more, and I learned more about his mental state and how he tried to quit multiple times but turned to videos to "feel something" because he felt just numb whenever he wasn't with me. As much as I could, I sympathized but ultimately ended things. It was the hardest thing I've ever had to do. We love each other so much. It broke my heart more to see my love hitting rock bottom in front of me, but I knew I couldn't stay in the relationship as it was. He needed to work on himself.

In our last conversation, he was so adamant that this time, things would be different. I want to believe him. He had already scheduled another therapy session by the time we talked again and said he would actually make them more consistent. He was in the middle of buying a house but chose not to so he could focus on healing instead of introducing the stresses of home ownership. Considering how much he worked to save for a down payment and was really excited about owning a home, I know this was a huge sacrifice. He says he still wants a future with me but knows he needs to change before he has that future, with me or with anyone. I want to believe the timelines I see of like 3-6 months to reset brain receptors or whatever or even to 14 months until being almost fully reset and more "normal." I want to believe that once he gets there, he'll be good and we can make our way back to each other. (Earning my trust would come then.)

This also feels too naive and almost too easy. Because his issues have been around so long, I know it'll likely take much longer. I'm not waiting around for him. But I just... I miss him and just hope that magically, he'll be on the shorter end of all and maybe we'll both be healed at about the same time and can start clean. I guess we'll see.