Why do I get butterflies every time I seem my ex, a picture or even when people say his name!?

its been 5 months since we broke up. He is dating a new girl now... and I think I still have feelings for him. I actually can't stand it. I'm not obsessed with him, and the fact that he's with another girl doesn't really bother me.. its just the fact that I don't even know him anymore, and he just... Show More