When do you guys use “that thought is irrelevant” vs “maybe, maybe not”? So confused

I see a lot of posts and comments here along the lines of... "the thoughts/urges aren't you -- they're just OCD." Though this is often true and comforting, isn't this just a form of reassurance? The way to beat OCD is by accepting that the distressing thoughts MAY be true/real, a.k.a. "from you" or "not just OCD." By brushing distressing things off as "just OCD," you excuse the thoughts and therefore feel reassured. Obviously it is good to be aware of what OCD does to you and know when you're experiencing a spiral, but crediting all distressing thoughts to OCD is a way of finding certainty about them. What do you guys think of this? Am I right or wrong? This is just the way I think about it, but I see the "this is just OCD" thing so much on here and I often wonder if that is a form of reassurance.

Today, I accidentally said "sit with the thought and let the thought be there." And now I'm obsessing that because I used "and", that now "sit with the thought" and "let the thought be there" mean two different things. I should have said: "Sit with the thought. Let the thought be there." I'm afraid that because I said sit with the thought AND let the thought be there, that this means make the thought real 😞

I know the solution is to always say “yeah that could be true, but I am choosing to live my life anyway.” However, I feel like my biggest issue is my brain always assuming that it is immediately true when I do that. Like if I say “maybe I’m attracted to teenagers, it’s possible,” then my brain INSTANTLY starts rationalizing that thought and defending it and being like “oh okay so you think this now and it makes sense because xyz, and now that’s who you are and your real desire is now and always will be teenagers.” I feel really alone in this area of feeling like my brain “accepting the thoughts” means my brain immediately accepts them as true. I obviously don’t want to think they’re true but I feel so stuck now.