I need some help in fixing this mess

What can I do? I got drunk at a bar last night and flirted with some guy while my boyfriend was there. He’s really angry at me and I regret it so much because that’s not me as a person. I love my boyfriend so much that Id do anything for. What can I do or say. I love my boyfriend so much and I can’t believe myself for doing this to him. What can I do or say to make this better? He doesn’t want to talk to me right now because he’s so angry