Ask your friend what the full story is explain what happened as much as you remember and try to piece it together also we all make stupid mistakes until we find our limits apologizing as profusely as possible and offer to take him and his gf out to dinner or something to apologize.

It’s a process. i didn’t have breakthroughs in any areas until I got a therapist that turned situations or memories upside down with her questions. Maybe a session soon will Surprise you. Best of luck.

It's the drinking. Some people just are mean drunk. Do not get drunk ever again. If you drink just limit to a drink or two and just state that you won't drink anymore due to what happened last time and just stop there. Do this friends drink a lot? Do you?

I see that you contradict yourself in your statements: "I am not mean, I am a good friend, I am a nice person. Don't know where this came from" and then you go on to say you have a history of violence when you were younger... or at least a history of being mean. So you do know where it comes from, and there's more from where that came from. In therapy go through this and the unresolved trauma because your inhibitions disappear when drunk and that's why your mean behavior came back.

As for your friends... you need to apologize profusely. Sit down with every single one of them. Go through the behavior. Accept responsability, say you are going to therapy to address that issue and you are committed to work on this since it was not ok and it hurt people you care about. Finally, offer restitution. How sre you going to make it right by the people you hurt? Maybe some dinner and just go through the whole process of... being in the dog house as it were, since your stunt hurt people. Just be patient with them and with yourself. You made a mistake, a big one but you are a human. Just try to make this right.

it's probably the alcohol, I stopped drinking after a similar experience but I got mad at some neighbors for doing some shit they shouldn't have been doing but none the less, I didn't act properly because of alcohol. I got mad and wanted to fight and yell because I was drunk.

There's a few sentences from your original post that you should show your therapist. It starts with "I'm glad I kept myself distance from them". You might be self sabotaging.

Talk to the therapist about attachment theory if they're into that. It helps me figure out what my emotions are making me do sometimes when my own responses confuse me.