I have ROCD, can't tell what is OCD or not

I am new to OCD. It's been liberating to know that I have it, it explains so much. But I am really really struggling because:

I was married. We were completely in love. We were extremely young and together for 3 years total. Admittedly, he has barely any experience in friendships, relationship, anything sexual before me. I on the other hand have experienced a very different life from him.

Last summer he discovered that I kissed someone during our talking stage (we liked each other, didn't meet in person yet). He was completely devastated, felt it was a betrayal and almost broke up with me but didn't.

This flipped my world upside down. I had no clue that people considered kissing before any established loyalty agreement cheating. I knew it wasn't GOOD, but I didn't think it was considered wrong by most. I want to say I am an extremely loyal, almost paranoid level partner and always have been. I wasn't aware that anybody thought that it was cheating.

I became extremely obsessed with the thought, and I kept thinking about it until I remembered when I was extremely drunk I could have kissed another guy. I wasn't 100% sure, but pretty sure. At this point I had already realized I have ocd. So I had no idea if this was rumination or breaking his boundaries. I told him, and he broke up with me. There is a possibility maybe in the future we get back together, we really had such a good relationship and this completely broke him. The possibility that we might be together again just makes me worried, I already can't stop developing new thoughts to confess. I keep searching for things...

I feel like people are able to move past ocd by knowing for a fact that their partner wouldn't think much of their confessions, but what happens when he reacts and does think it's bad? I just don't know it's ruining my brain.