I'm going to continue to sleep with a girl I'm embarrassed of out of loneliness/boredom
Why are you sleeping with someone that you are embarrassed of?
I don't even want to see her ugly face anymore and I can't find another person to sleep with, otherwise I will end up fapping
You shouldn't lead people on and use them to cure your loneliness. Masturbation is an acceptable practice that won't result in hurting people or using them.
Don't you think it's normal for guys to get some on the side?
Your gender has nothing to do with being responsible and mature. You should never use someone for sex, unless you both agree that there is nothing more going on. If you don't improve your mentality about this, you will find yourself alone.