Help with my exboyfriend. I love him

Elizabeth
So I'm attached to my first love, the guy that took my virginity and the one i thought was the love of my life. I dated him on and off  for 9 months and he cared so much and he loved me but the last 3 months he started lying to me and we broke up. We ended up in really really bad terms. We didnt talk at all and when we saw eachother at school we ignored. And now, 1 month later I miss him and we dont talk but he posts this stuff on facebook saying he misses me but I can't go back to him. I mean I know whats good for me and whats not. But I dont know what to do because I love him and i cant talk to any other boy because i still think about him. Please help me give me your opinions.
Ps: on Thursday is his birthday. Should i wish him happy birthday?