Keep in mind that I don't know if I actually have avoidant personality disorder. My psychologist suspected it, and everything on the wiki page sounds very familiar, but I haven't been diagnosed with it yet.

I've had very low self esteem for years, and no matter what interest or hobby I pick up, it always turns into an obsession at some point. As soon as a little competition comes into play, it's like Pandora's Box is opened: I perpetually think about other people with the same interest and become more and more scared over time that I'm really bad at it, never going to make any progress again and so on. This makes me like the hobby/interest less and less over time and ultimately give it up. That's happened two times already with different interests.
I find myself avoiding people or places that remind me of my obsession, as weird as it sounds. Although I can be really interested in something, after some time I just get afraid of competing and compare myself to others. Then it turns into some kind of love-hate relationship.

My problem is that I turned my passion/obsession into my course of study. That's the reason why I had to interrupt my study for the second time now. I begin by making everything about this obsession, then get terrified more and more, avoid it altogether by procrastinating and not talking to people and then move on to something completely different. Just to avoid my fears, to run away.

Again, not really sure if that's avoidant personality disorder. I was diagnosed with OCD as a child as well, but that went slightly different.