Hi Jamie,
Obviously, we’ve been given a very small snapshot into your relationship so it’s hard for any of us to make big decisions like “leave him” on your behalf.

I think their are two issues at play here.
1. Your boyfriend is abusive.
Your friends are the best litmus test here.
If he’s a jerk and making you feel bad then I agree with Anita – there are better fish in the sea.
But if he’s a cool guy and you trust him and he’s just acting like a jerk because we all say dumb things in the heat of the mo’ and you wanna see your relationship work, then that’s cool too.
It’s your decision but I wouldn’t get too hung up on the one guy.

2. Cheating
To me this is a separate issue and I got some really fantastic advice on the subject.
A relationship is all about trust. Breaking that trust is the cheating part.
If my GF got drunk and kissed someone, I would forgive her because we all do dumb things when we’re drunk.
Just cause we’re in a relationship doesn’t mean we can’t get a crush on another person / always be devout.
But if she saw that guy after that night, I would consider that breaking the limits of our trust.

If you want your relationship to work, I would highly recommend cutting ties with that boy you kissed.
Having him in the picture hampers the trust your bf can put into you and will stop him from moving on.
Good luck dude and be mindful of these relationships on your health.
Have fun, as soon as these relationships affect your health, they ain’t worth your time.