What now?

Thing is this new yearz was a little crazii me and my ex boyfriend who were tgether for about 3 years on and off has been rumored to have gone out or done something with a girl named alma. Now and new yearz she appeared out of nowhere and since his family and my family are intertwined we constantly see eachother at family events and holidays. But she showed up out f nowhere no one invited her and he didnt even pay attention to her. Now she I think was jealuos because im a pretty good dancer and he just kept looking at me and we happened to share half a dance together well thats beside the point she kept dancin with little kids around his table I think this was to get his attention and I guess it worked because they danced twice now I dont know why I cared I really dont have feelings for him anymore or so I thought well then I began to drink baileys smirnoff vodka tequila shots you name it I drank it and 321 new yearz passed I said happy new yearz to everyone except him I wanted it to be private because of last years new years well anyway im waiting by a staircase and she pulls him by the arm s im kind of pissed and then I go upstairs to take my friend to the bathroom by the way the party was in a basement and she goes upstairs now im waiting at the door of the bathroom when I go to leave I see her kiss him it filled me with anger and then she pulled him to his room they didnt spend much time there so I know nothing went down but it doesnt matter I was mad so im sitting in the stairway with my friend and she passes with a smirk so I get mad and curse her out while shes passing she doesnt pay any mind to me so I go after her t hit her and I dont know how I got to the roof but yeah anyway I was drunk I dont know much of the future details but I do know that I fudged her up and she is really badly messed up and I dont know what to I feel like apologizing but I think she kind of egged it on to become more than what it was and my momz was there and my cuzns and every1 is telling me that I shudnt say anything she deserved it also I was drunk but I don't know anyone have an opinion on what I shud do I feel like getting over him but how hes always at the family parties or he comes by my house its weird I try to get him out of my life or at least I think I try im really confused can anyone help me? I ask this because lately I've been wanting to see him I know where he hangs out and I kud easily make an excuse and tagg along with my mom to go eat lunch at his aunt restaurant where im 100 percent sure hell be there I mean I know I blew it but then again I feel like im over him but I wanna see him to make sure but I dont wanna hurt again if I do have feelings for him. What to do?