Advice ? Help

I was with this guy for a year and we broke up bc he was cheating on me and he had been keeping a secret from me for the entire time of our relationship (he's bi and he lied about it to me ) and we broke up like 3 months ago but I'm still so in love with him which is horrible and I think he is talking to another girl right now and it is literally killing me and idk how to get over him please help .