Struggling with Real Event OCD and Intrusive Thoughts

(CW// intrusive thoughts) Does anyone struggle with real event ocd? I am not diagnosed with ocd myself, but I do have autism so I struggle with obsessive thinking. Lately I’ve been stuck on events from the past and struggling to remember what happened/reassure myself that I’m not what my intrusive thoughts tell me I am. But I hear that it’s not good to validate your thoughts by rationalizing them? Which is something I find extremely difficult as my autism makes me very focused on understanding why things work - so I NEED to figure out the truth? All I can think of is what happened and I’m constantly trying to recall things from 3 or 4 years ago. I know I am not a bad person like I tell myself and I have definitely proven so to myself - yet I still can’t let go of the thoughts and they are so overwhelming I don’t know what to do anymore!!! Why can’t I trust myself? And how can I ignore these thoughts?