Why is it the only think I think about?????????? How can I convince myself it isn’t true when it feels so real??????

When an intrusive thought comes I can’t just say “that’s not true” and just move on. I always feel like I have to disprove the thought and be able to say it with confidence but the problem is that the ocd doesn’t allow me to feel and say it with confidence so I get stuck for hours or even days. How can I stop feeling like I need to do this?

I know he’s not cheating on me. He’d never do that and, as hard as I try to tell myself “he’s proven already that he’s not” and show myself all the signs of commitment and dedication, I still have that fear. It’s eating at me and ruining my relationship. How do you guys get over this? If my brain were true he’d have been cheating on me for months in ways that aren’t even possible. It doesn’t make sense if I think about it logically but it seems like when I do, I create in my head more ways for it to be logically true. What is your advice? How can I stop self sabotaging?

Does anyone have any advice for how to know the difference between ocd and real feelings/thoughts? Sometimes an intrusive thought will come in and I immediately know it’s ridiculous and I can just leave it alone and it won’t bother me but other times I really really don’t know. It’s when ocd hijacks and twists my real feelings and thoughts and tries to manipulate me into believing they’re something they’re not or something that doesn’t align with my true morals or intentions. But since it’s twisting and mixing with real feelings I get so confused and scared. Everything gets jumbled and I feel like I can’t trust myself or my own mind. Yet other times and other topics I can laugh off and push away just fine. Make it make sense. And then I start to think well maybe I don’t have ocd at all and I’m just in denial because I don’t want to accept that these scary/concerning things are true about myself. Or maybe that’s just the ocd talking.