retroactive jealousy OCD

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?

So i had really bad pure ocd but recently it’s been sooo much better but i’m in a relationship and me and my bf dated before about 2 years ago then we broke up and now we are back together but i’m having an issue where i will try to go back years and find something i did wrong and i really do not want to find anything to feel wrong about or guilty specifically something i may have done wrong to my boyfriend but the thing is i’m a good girlfriend and i’m very loyal so i don’t want to ruin something for me because of my past if that makes sense like i can’t remember doing anything wrong but my brain keeps going are u sure let’s look at all your interactions with people and it’s so annoying i just wanna live my life in the present does anyone have any tips

I’ve been really struggling the last week and I need some help. I’ve been seeing a guy for about 2 months who checks a lot of my relationship boxes. He’s so kind and we have a lot of fun together. The first few weeks I was totally smitten but had moments of fear about being committed. We talked about it and decided to take things slowly, and then I would have days of feeling like every thing was perfect with some fearful feelings in between. Two weeks ago now my SO-OCD and ROCD started to come back a little as well as my more anxious-avoidant behaviors. I started to get more scared of the future and it was more intense. At the end of last week, he asked me to be his girlfriend and I said yes. He is exactly the type of person I see myself marrying and has great values and is so secure about me. Until last week, he generally made me feel so safe and secure. Ever since saying yes, I feel so scared and anxious and my SO-OCD and ROCD is on max. I also find myself getting more annoyed and irritated about things that were minor annoyances or non-issues before. I’m having intense physical responses to both OCD themes, and the nagging thought and feeling that I need to end things with him because we aren’t right for each other. It makes me feel so sad and guilty. Sex is becoming harder because of the thoughts too, whereas at first it was perfect. I don’t know who I can talk to about this without them telling me to just break up with him. Everything is so new so I think they’d chalk it up to my intuition. But I do want to be in love and have less fear around relationships, so I don’t want to give into the fear. I think it could help me to set boundaries and have space for myself more often. I think I need some advice or insight. I know I shouldn’t ask for reassurance, but having some around how other people have felt at the beginning of a relationship would help. Why is it that the label is freaking me out so much? How do you guys set boundaries to prioritize yourself when you feel this way?