How do you fight it?

I’ve been struggling with depression lately. I’m going through family problems and I stayed single for a year to get over my last ex and to find myself again. Recently this guy that has had a crush on me for awhile just got out of a relationship. He invited me over and we’ve been hanging out. Then, we just had sex. It just happened. Things were going really good and he was being really sweet until recently, in fact, he’s being a complete asshole. I have known him for awhile so therefore I kinda started to get feelings especially with how good he was treating me. I feel as though I’m not enough for him and I feel like he’s going to cut me off as easy as every other guy in my life has. I have trouble with my friends because they’re all in relationships and are occupied all the time, I feel like I’m alone. How do I cope with this, I’ve been feeling it for awhile and I thought that maybe talking to a guy would help but he made it worse because now he’s just being a complete dick. I feel like he got what he wanted and left, I feel like such a victim.