Failed relationships

Hi, i'm new in this page. I just admitted that I got a problem with my personal relantionships because of my porn and masturbation habits. Since my mother died, when I was 12 (i'm 22) I started watching porn and jacking me off, at firts it helped me to quit or avoid stress and anxiety, then I create the habit of masturbate daily or even chat with random girls (i'm straight) for sexting. When I'm depressed or anxious, I search for some porn or girls to chat with, sometimes I could be agressive with them, but once I finish, I feel bad, and guilty. My biggest concern is my girlfriends relationships, I usually don't enjoy sex with them, its not easy to get an erection, and I keep sending messages to other girls while I'm dating. So I don't want to commit cheat, I just want to reboot my sexual behavior, to get better my sexual and sentimental life with my girlfriends, instead of pleasing my bad habits and impulses.