I need comfort. Please, I'll answer any of your questions! Friend betrayal, and bf issues, helpp please! 10pts?

So my Boyfriend liked his ex so I broke up with him and he has been flirting with my bestfriend since we broke up after his ex wouldnt take him back. He still likes me and I think he's just hurt. But yesterday he went to the park alone with my best friend... when we went to the park we made out. He made sure i knew to. He also thinks im going out with a kid that is just my friend. So what to do? Who do I forgivee? My ex bestfriend betrayed me, she's a backstabber to do that to me, dont u think? Thanks for all your help! We broke up like 3 weeks ago, do u think he still likes me?