Not quite a lover

I can't quite use the term lover for us cause we were never together to begin with or idk. I've been on and off relationship with this guy for 3 years it always starts around October and would end on December 28. Idk why I keep seeking him or whatsoever and I don't quite get why he's also like this as me. Everytime I got into a relationship I can't quite enjoy it to the fullest it's like there's always something missing. Everytime a guy would fail me smh this guy never failed to catch me. It became a cycle that I wasn't scared any longer of having a failed relationship but rather scared of him actually get tired of me at some point. I can't understand him at all, I can't understand myself either. I'm about to get bald spot sooner or later