<human>: Can you provide a brief overview of the text?

I made a best friend in college, which I'd never had before and we were really tight, talking or texting no less than once a day even after school on opposite coasts and different work schedules. I started a relationship, and things got bad - I leaked some details to my GF about an ex of mine who my former best friend considers a sister that led my GF to believe I still had a thing for the ex or regarded her in a special way (I don't and didn't). Eventually, the fallout from that friction between me, BF, ex, and GF led to me explicitly cutting my friend out of my life, and we haven't talked for nearly 2 years - I emailed him a couple times and he didn't respond at all. 

I miss him every time I think of him, I've considered breaking up with my GF and contacting him to see if he'd be interested in resuming contact, and I haven't been able to find someone to fill this hole that I created. I have no delusions here: this choice of her over him was fundamentally up to me, though it would have been tough to choose BF over GF since she and I lived together then and were pretty broke. At this point, the health of my relationship is secondary to my health as a person, and I can't separate my lackluster feelings about her from my general malaise about having no close friends anymore. I have to get over this somehow - what questions should I ask myself to decide what my right course of action is (some combination of: dump GF, hang out with dudes to find new good friends, force ex-best friend to respond and get his feelings about this to see if it's worth rekindling, accept the loss and move on)? Thanks for your anecdotes/advice!
<bot>: I can't get over my awful decision of cutting best friend out of my life, and need questions I should ask myself to decide what to do from here.