Constant ruminating over bad memory

I’m at a loss about what to do. I’ve been with my partner for about a year. I’ve wanted to be with him for 3 years and now I finally have him, I got out of a really toxic 11 year relationship about 4 years ago so I’ve had plenty of time to heal, things where going so great at first in our relationship and I’m still very much happy with him, I love him more than anything, but the past 5 6 months I’ve been having a constant fear that he’s gonna cheat or watch 🌽behind my back any chance he gets , I know that’s a touchy subject for some, but me personally it just makes me feel that I’m not attractive enough,or feel like I’m not good enough, I’ve never found evidence of cheating, and I’ve found 🌽 in his history once but I told him how I felt and he told me he understood how I felt and wouldn’t do it again,and I know the constant asking everyday and needing for reassurance with it is putting a tear in our relationship, I just want to fix it. Does anyone have any advice on how to redirect my brain whenever I start overthinking about it when I’m not around him? It just puts so much stress on me when I’m not around him cause I’m just constantly in my head about it.

Ive been having terrible irrational thoughts that Ive cheated and don’t remember. Like the guilt made me repress the memory and im actually an awful person and someone’s gonna expose me. I know it’s not true and I love my boyfriend more than anything but i feel so guilty for something ive never done. its been making my life so difficult and i dont know how to explain it without sounding like im covering something up :( Its making me think that I need to break up and i don’t want too, but the guilt and anxiety is eating away at me. I feel like I need to get better before I continue on or i’m going to permanently ruin everything with my mental illness

the most debilitating ocd flare-up i’ve been having for the past few months has been about the guy i used to talk to. we weren’t dating per-se, but whatever was going on between us was very confusing and unclear, and it ended up with me being very hurt. he was basically leading me on, and couldn’t commit to me. it’s been months since we’ve stopped talking and i still can’t stop thinking about him. i don’t even care about him that much in an objective sense, but i am genuinely obsessed with him. everything i see reminds me of him, and my mind is constantly running through thoughts about him and our situation — why did it go the way it did, what did i do wrong, does he still think about me, etc. it’s honestly so humiliating and makes me feel pathetic because i know he’s probably moved on by now, and i still can’t handle the thought or sight of him. i just wish i could stop ruminating, because it’s gotten so bad that i can’t focus on school or anything else in life. it’s so constant to the point where, when i bring it up to my friends (which is very often), i’m met with concern and even frustration rather than sympathy. how can i cope with the rumination? it’s genuinely exhausting, and i can’t sleep at night because my brain is just running like a motor. i have dreams about it almost nightly as well. anything helps!