Emotionally gone

A couple weeks ago my boyfriend and I went on a week trip to Florida. I thought we were going to spend all the time together because he’s leaving in March for basic training. I was wrong the only tone we spent quality time together was when we were in the room and walk around a bit and have breakfast. Other than that he had friends come visit and left me in the room two nights in a row to go party. We come back and he tells me I should give him space so he can miss me. The last time he said that was when he cheated on me before. He comes for a hour at my place than leaves. He says he’s doing Postmates but instead he’s at his friends house which I don’t like. He cheats on his own gf and is a low life. Everytime my boyfriend is there there’s a girl 50% of the time. I calmly called him out about it today. He got mad at me and tried to argue with me when all I did was speak calmly. He does this when he’s guilty about something. He says I’m insecure because I have a lot of growing up to do. I’m 20 and he’s 21. I’m insecure because he cheated on me with a light skinned girl and all of the girls he was wit is light skinned and I’m brown skinned and I’m insecure. I barely talked to him today and I would usually go to his place to surprise him and talk but I didn’t. I’m emotionally drained and I can’t take it anymore. Everytime I bring up the cheating he says that’s irrelevant and I have issues. I just want answers and it seems to me I won’t ever get them. I’m so torn on what to do because I can’t keep putting myself through this anymore. I wanna be how I was a year and a half ago.