How do you "sit with the anxiety"

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?

So maybe the title wasn't the best to to put it but when you guys start having obsessive thoughts how do you stop them before it turns into compulsions and anxiety?

I cannot for the life of me stop ruminating or checking how I feel about thoughts or focusing on thoughts or creating more thoughts. I feel like I’m losing my mind. I want to scream. I try not to ruminate about the thoughts, but trying not to just makes me think about them more. I try not to check, but somehow, I still check. I want to let a thought sit in the background, but the more I try not to focus on it, the more I end up focusing on it. I don’t want the thought to expand because that feels like engaging with it, but I can’t just stop it from expanding. It feels impossible. People keep saying I’m in control of my compulsions, and maybe that’s true for the physical ones. But when it comes to the mental compulsions, I swear I have no control. It feels like I’m missing something that everyone else seems to have, like there’s some tool they’re using that I don’t have. Controlling mental compulsions has never felt possible for me. I’m starting to fear them. And every time someone says I’m in control and can just choose not to do them, I end up beating myself up even more when they happen. Or when I *choose* I guess. I don’t know anymore. If this is my fault, if I’m responsible for this, then what does that make me? I feel like a monster. I am at my wits’ end. How am I supposed to control mental compulsions when it feels like they control me? I freak out when they happen. They don’t bring me relief, they just make me panic. I want it to stop so bad.