<human>: 21F (me), 23M (him), 2 year relationship. My boyfriend and I have our share of problems, but I have recently come to terms with the fact that this is the root of all of them.

He knows I think this, and he does his best to assure me that it's not true. He doesn't talk to her as far as I know. She cheated on him or something. In other words, I don't reeeally have any reason to think this. But for some reason I am completely convinced they belong together, and I make a big deal about every little piece of evidence I can find to support this theory in my mind. I'll admit that I think it comes from my jealously that he lived with her and took her on a fancy vacation when they were together, which is not the case with us. Note: He is my first "serious" relationship, I have never lived with anyone.

I know this is really really silly of me, but it's tearing our otherwise awesome relationship apart! I will refuse to talk about moving in together or getting married (some day) when he brings it up. Please help me reddit, I need someone besides him to tell me this is insane.

Summarize the given text in a few sentences.
<bot>: I have decided that my awesome boyfriend would be happier with his ex, and he can't convince me otherwise. Our relationship is at a standstill because of it. Help!