I love my bf so much and hes so perfect for me so why do i have ROCD???? Help

For the past 3 months ish I’ve been struggling on and off with this anxiety and fixation over my relationship. To wondering if i still have feelings for an old friend, wondering if i actually love him, wondering if the thoughts are all real and im just trying to cover it up with ocd. It sucks, when im talking to my boyfriend i feel fine. The words i love you and talks about the future come naturally. I can’t imagine myself with anyone but him. But this constant rumination on my relationship is KILLING me and I’m scared it’s going to ruin what i have. It makes me numb and disconnected which therefore makes me believe the thoughts even more. They just feel so real sometimes and it’s so scary like why can i not just enjoy it. We’ve been together for a while so i know there’s periods of like feelings ebb and flowing but this is so much more. It’s just constantly sitting on my chest with anxiety. My compulsions are coming on this app, looking at photos of us and confessing it to him. He’s very understanding and helpful. I love him so much. I just need help / I’m also just starting new meds as well ..

I'm 18, and been in a relationship with my man for nearly 2 years. I started living with him around 2 months ago, and all I do is think about if he's cheating. We were long distance for a year and a half of our relationship, maybe seeing eachother once every month or two. I decided to move in with him, and ever since all I can think about is if he's cheating or watching porn. When he's in another room I think he's doing something wrong, I have to check on him every ten minutes to ease my anxiety. I didn't have this problem before moving in. Granted he has talked to some girls on his phone, even having his ex on his phone (didn't do anything bad) and he is porn addicted though he is getting better for me. It's gotten so bad I want to leave him. A couple days ago I broke up with him and it absolutely broke my heart, I couldn't bare it so I gave him a month to show me he can do better, and for me to work on myself. If I'm still unhappy with us I'm going to leave. I love this boy more than anything. I'm scared to be without him, this is my first real relationship. At this point I refuse to even sleep until he is sleeping. I don't want to start over, I don't want to leave him, but I really can't take this pain it's causing me. It's all I think about. I've convinced myself so many times that he's cheating, but I know he wouldn't. I question whether it's anxiety or intuition. Maybe I just know deep down he really is cheating and I just don't want to believe it. I don't know. I don't think he would do that, but at the same time he's really into women. I hate that he looks at other girls in a sexual way, it bothers me so much, and we talk about it often, but with it being an addiction it's difficult. He has gotten a lot better since we have talked about it. He understands I have an issue and is usually happy to talk about it over and over and promise me over and over that he's not cheating. He allows me to have his phone whenever I want and everything, I have no reason to think he's cheating, but I can't get over it. It's not fair to him either. How do I deal with this? How do I stop hurting so much?

My rocd is spiraling so bad i feel like I’m terrible and can’t recover 😓 idk wuts real anymore yet ik i never wanna leave my man😓whats wrong w me