You know the feeling when a close friend of yours becomes friend with the person who hates you?

I know this is selfish but it fucking hurts so much. The person who broke you to pieces moved on without giving a shit and now is laughing,joking (doing the same stuff they did with you) with your best friend?. Yes I'm selfish but yeah it's hurting me a lot.  I keep telling myself I can move on and all but no it doesn't works cause I'm super weak

Okay I'm done