Some of my clients admit to self-loathing.
Okay, so do I. Despite my impressive list of accomplishments and current work, I honestly hate myself. I hate that I'm ugly, kind of a curmudgeon, and virtually a hermit. I overeat, am intense, am not quite as capable as I was just a few years ago. I hold libertarianish political views that most people hate. I roll my eyes at unthinking liberals who believe all wisdom resides left of center. I too often forgo tact and hit people between the eyes with candid input, often unsolicited. Plus I decry my aging self.
I'm well aware that my glass is more than half full but that awareness doesn't make me feel better. So I can't tell you to focus on your positives.
Perhaps like most things, the answer is simply self-acceptance. Loathe yourself if that's how you feel. Maybe, like me, doing that for a while will desensitize you, take the edge off your self-hatred. You'll still hate yourself but it will bother you less.
There is an important silver lining to self-loathing, at least mine: It motivates me to work ever harder. And indeed, as Michael Lopp, author of Being Geek told me yesterday, nearly every successful person in Silicon Valley suffers from the same malady. Indeed, no less than Abraham Lincoln suffered from grave self-doubt. The opposite syndrome--high self-esteem--usually leads to complacency and no growth.