How do you diagnose a sociopath?

What if the sociopath is you? I am about 79% sure I am. I have no problem making things up on the spot and selling my point (my mom, who I suspect is one as well, calls this the *sales* gene) I use people for my own satisfaction and the only reason I lead a semi decent lifestyle isn't because it makes me feel satisfied, but rather, I know it makes me look better in the eyes of whoever it is I hang out with. I have extremely shallow feelings tward everyone (sans my grandfather...the only day I openly cried in public was the day of his funeral) I constantly feel bored and create *drama* just to get rid of it and look like the hero. I never do anything for anyone unless I feel it will benefit me in the future. I am a people watcher and have been mimicking accents and facial expressions ever since I can remember but I still get confused about reading people once in a while (this botherd me to the point that I actually thought I might be slightly autistic). I only feel enraged and embarred when caught in a lie or when I can't impress the *victum* <- thank you internet for making sociopaths look like a blood thirsty killer.- I hate to lose and I gloat my victories. I have been known to be manipulative and uncaring. My last relationship was full of drugs and alcohol which I used frequently so I could feign emotion... I am an alcoholic, I'm abusive and most importantly of all, I never feel bad about making someone feel terrible. I only say sorry when I might need to keep that person around for something and I never truly mean it. I actually delite in tearing people down and making them feel worthless if they double cross me. (By double cross I mean things people normally would just get a tiny unnerved by sets me on a rampage) the relationship I referred to ended on what should have been a mutual note. He was moving and didn't do long distance. Fair enough right? Instead I made him fall in love with me (intentionally) then ripped hm to shreds.