I had a bf for 5 yrs yeah we fought we broke up alot but we always got back together i kknew no matter what?

what we would always be together. teh longest we ever broke up for was a month or 2. until one day he just told me he found someone else i was devistated thought he would come back. 3 months after he text me with he still loves me but it will never work and things will never change between us we trid to be friends but all we did is fight. it now has been 6 month and yesterday was my bday and all my friends threw me a party and after me bein there a couple hours he walks in i was so shocked i couldnt even move i just started crying. he told me he still loves me and cares but nothin will ever change between us we have too much of a past. he also said he loves his new gf and hes not going to break up with her. later that night we all ended up drinkin we ended up having . im so confused if he didnt care why would he of showed up to the party in the first place? and he obviously doesnt care that much about his gf cuz he cheated on her right? i realized i cant live without him and i hope he comes back but im so confused?????