It can sometimes be a case of selective observation. My dad tells me, by way of example, that all Asian people are bad drivers. He's figured this out over a long long period of observation of other people driving. The problem is that he mentally logs it in as "Yep, I thought so", when he notices an Asian person driving poorly, and if it's not an Asian, it just doesn't register. So he has this really long, carefully constructed list of BS data.

I'm not saying that what you're going through isn't bad, of course. But I often get a bit of a mood boost when I look back on my own times and remember the parts of them that weren't bad at all - watching X-files with my friends, sledding down hills on cardboard, playing catch with the old man. I just don't remember them as often as I remember the other stuff (examples withheld), and so it distorts my perspective.

Again this may not be happening to you, but it's worth cogitating on. At the very least, you can say that it's about time you started replacing some of those painful feelings with good ones, starting with a hug from a concerned and friendly e-friend.

*hug* - hang in there, k? I'm only out to get you happier =)