You will have to accept that it's not going to be easy to make changes but that you can do it. You are surely not as terrible, pathetic, worthless as you are making yourself out to be. And like Red Panda said you might never feel completely comfortable getting a haircut or ordering food at a restaurant but you can definitely do it and you will get more slightly more comfortable with it each time. Maybe on a given day you will feel like you can't do it, but just take the day off and relax and psych yourself up for doing it tomorrow and don't let yourself cop out on it the next day.

I am really socially awkward and I hate dealing with people and all of that, but I do have one guy who I would consider a good, true friend (he's different than me but not "normal" by societal standards either). There are lots of different types of people out there - it's not like everybody else is "normal" and you're a total failure because you aren't perfect and have some issues. There are people out there for you to be friends with or have a relationship with. Personally I wouldn't really be able to be friends with and relate to someone who is stereotypically "normal".

You're only 25 so it's not exactly too late for you - if you were saying this at 50 I might be more inclined to think "well, guess you just gotta suffer out the rest of it" and I might agree with the "waited to long" statement, but really you didn't. I wish I would have gotten therapy as a kid and it would have maybe changed life up to now for the better but I just wanted to deny anything was wrong and just push on as best I could. But I'm almost 30 now and it's as good a time as any to try to make some progress toward being happier.

There's a reason you are where you are today and it's not 100% your fault - you didn't just choose this and then end up here. Clearly there is an underlying reason for this that was out of your control. Nobody chooses to end up as AvPD - I think it's safe to say that we all tried to cope with life as best we could and ended up like this. You are deserving of sympathy just like the other people here are, as are all the other people who ended up as avoidant because it was the only way they could cope with X, Y or Z happenstance of their life.