Why does he joke about being with other girls?

I called my boyfriend on my lunch break today and lost connection. I immediately called him back and he seemed pissed bc I “hung up on him”. I get home from work to my him leaving to go play hockey. I asked if I could come and he said “no, you hung up on me fuck you. How am I supposed to get bitches if you’re there?” Then he left and returned about a min later because he forgot something. Then he’s like “something wrong buddy?” I was like “nah, you wanna fuck other bitches? Go ahead” and he told me it was a joke. OH MY GOD THATS HILARIOUS HAHAHHAHAHAHAHA. What a comedian. I’m dead.
He says snarky shit like this all the time & gets upset with me when I don’t take it lightly. Why does he say things like this? To make me upset? It can’t actually be to make me laugh. I know other girls that do laugh it off, but at this point I’m tired of it.
Why does he joke about being with other girls?
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