how to get over him

My first love and i broke up almost 4 months ago ,, we were together for a year and a half .. every time i see him i try to make it look like i'm happy but i'm actually dying inside . 
these four months i've been trying my hardest to get over him by surrounding myself with people who love me and and care about me but nothing seems to be working . today i saw him and i instantly started crying my best friend started comforting me and telling me it's okay . a few minutes after that i texted him and told him i felt about him ,, but he said he doesn't like me but he'd take me back if it weren't for some actions that had caused the break up .. and all i've done is cry since i've left my friends .. 
can someone please tell me how to get over him like he got over me ..
i'm tired of loving him and not having the same feeling felt back ...