Real event/False memory

So, I know my capacity to get fixated on things. And it's normally something that's relatively remote but, my latest issue is really getting to me and I was wondering if people have any advice. I'm avoiding getting too into specifics, as I don't want this to get reassurance-y but, in essence.. I came to the realisation recently that people who I'd been "friends" (feels like the wrong term now) when I was younger were not very nice people, and normalized a lot of very unpleasant behaviour towards other members of the group. They really normalized it, sold themselves as figures of authority, as older and more responsible and grown-up than others, and looking back, they acted horribly. And coming to this realisation, that I'd been manipulated into just accepting their behaviour has just... broken me. My OCD has latched onto it and I can't stop feeling irreversibly tainted by it. I've talked to others about it, and they've reassured me, told me it's not a big deal and that I hold myself to too high a standard, but none of that sticks. I feel better for a bit, then think 'Maybe when you told them you were skewing it to make yourself look better' or 'Did you leave out a crucial detail'. I keep ruminating over and over, trying to remember exactly how everything played out, trying to figure out if I fed into the behaviour, if I did something bad myself (because y'know, I feel like I was accepting of it at the time, so what does it say about my own values?). I know I need to stop doing all this if I want to improve, but then some part of me keeps saying 'So, you're just going to let yourself off the hook then?' Normally, I can rationalize my own fears to some degree, assure myself something won't happen, but the realness of the situation, and the fact I only came to understand the reality of it because the thought had been bothering me means it feels so much more all-encompassing. I know confessing in itself is a compulsion, but I keep feeling that if I'm not I'm somehow concealing what I 'really am' from others around me, and any positive interactions are me deceiving them in some way. I feel like I can't enjoy anything in life right now, and a good part of me feels I should not enjoy it ever again. If anybody has any advice on it, I'm all ears. Or even hearing if you relate to these feelings, I might appreciate the solidarity at least.

(20f) I have been dealing with severe OCD symptoms for as long as I can remember. I recently got diagnosed about a year ago, and even though I know that these thoughts are probably my ocd, I still cant shake them. Growing up I was always very sexually curious. I was sheltered from a lot of things, as I went to a private school and things like sexuality and sex were never talked about. I remember doing some weird sexual things growing up (never affecting another person), looking up taboo sexual things, etc. I always seemed to become aroused no matter what the situation was, even if I just saw someone getting changed. I have no recollection of being SA'd, so i'm wondering where this all came from? Was I just curious and wanted to experiment and try different things? Or am I really a pervert, pedophile, etc. I have all these thoughts racing through my head and it's killing me. Everything I did as a kid I look back on and am disgusted, as those don't align with my views at all today. I never thought growing up thinking these things were wrong, or actually realize what they were until I got older. I'd like to think it was just my curiosity, but i'm not sure. What if i'm in denial and actually do like these things? I just need to know if theres something wrong w me, I cant keep going on like this. Could really use some advice.

If I cheated on my boyfriend or did something unloyal , would it come to mind 8 months later? Wouldn’t I have felt and known about it and that it was wrong the second it had happened ? If I wasn’t worried about it 8 months ago, should I worry about it now ? I have major ocd involving cheating and relationships and self doubt .