I don't have any stories on my end because I was that terrible bitch ex in high school who didn't know how to properly communicate that our relationship was over
I guess the one that I can consider "his fault" was my grade 11-12 boyfriend - he really hated one of my best friends for some personal reasons he didn't tell me about until way later, and he was just constantly suffocating me and making me feel bad for basically being friends with this guy, texting me like "when are you done hanging out with him", etc.
And it's not like I didn't try to solve this, I talked to my friend, I talked to him, I'd invite him to hang out with us too so he wouldn't have to worry about things, but he was just incredibly negative and bitter about my friendship. Prolonged jealousy is so incredibly unattractive - after a while I realized he was very different from the guy I liked in the first place and I just didn't enjoy his bitter company anymore, so I broke it off.
embarrassing aspects of him: he was loud. he was so loud. I was always embarrassed of being in public with him.