idk what’s happening

my boyfriend and I have been dating for a year and a bit and I feel like things have changed between us. He’s always blowing off phone calls now and just being in general an ass to me. He spends all his time with this one friend and he really hates me and whenever he slags me off my boyfriend never defends me.

I’ve tried explaining it to him but he gets shouty and doesn’t listen.

Any advice