We were drinking, and it just happened. We each confessed to our respective significant others. This is the worst thing I've ever done in my life. I can't describe the remorse I'm feeling right now. I feel like a complete waste of life. Me and my (now ex) girlfriend are best friends with him and his (now ex) fiancé. I was supposed to be the best man and my ex was supposed to be the maid of honor in their wedding. We've been friends as couples for 6 years. Our lives are so interconnected. Six months ago my friend and his fiancé were having huge, almost relationship-ending problems, and i was the one of the main people they both went to for help. Recently, my girlfriend and I had been going through problems, and they were the ones that each of us went to for help. We've always there for each other; literally inseparable. Do everything together. Go out to dinner together, sleep at each other's places, go on vacations together. It almost feels like we're one big couple sometimes. But not now. I literally just ruined everything in my life and the lives of all the people most important to me. I can't cope with the guilt. I wish more than anything I could take it back. My ex said she never wants to see me again. I tried to apologize to her, but to no avail. I keep trying to call my friend to beg his forgiveness, but he (understandably) won't pick up the phone. I even texted him to say where I was going to be in case he wanted to come and kick my ass (he didn't show up). I want him to; I wouldn't even throw a hand up to defend myself. When I was a teenager, my mom left my dad for one of his friends. I took it so hard. Fell into a wave of depression, started using drugs (long time ago). I spent my entire adolescence hating that guy, wanting to kill him, and wishing all sorts of bad things on him for the pain he caused to so many people. I swore I would never do that to someone. In the final analysis, I am no better than that piece of crap. I simply don't know what to do. I feel absolutely horrible for the pain I've caused to my ex and my best friend. I've never been a backstabber before, and it feels so terrible I can't even find the words...