You asked how you can find friends. Here is my suggestion for a long term plan:
1) turn off the computer, put on some running shoes and go for a jog. Do this every day, and try to build up your distance. Get exercise. Research has shown that teenagers (even NT teens) have the lowest levels of some brain chemicals like dopamine, lower than adults and lower than younger kids. It has something to do with the stage of the brain’s development. What it means for you is that your brain has poor “shock absorbers,” so teens feel every bump and pothole in the social highway much more acutely than older people. You can help strengthen your shock absorbers by getting regular, strenuous exercise. Exercise helps the brain produce some chemicals that help you feel better.
2) turn off the computer and get some exercise. When you are sitting in front of a computer playing games of aggression, your body is flooded with the “fight or flight” chemicals that were designed to rev up the caveman’s system enough so he could escape from (or slay) the saber-toothed tiger. But escaping and slaying both took a lot of energy that burned off those chemicals almost as fast as the body could produce them. With computer games, you get a lot of chemical production with no burn-off. Put on your running shoes, go outside, and do some temporary “escaping.”
3) when you feel your shock absorbers have become stronger, and your moods smoothed out more, find an old fogies club to join. A rock hound club would be perfect. Rock hound clubs typically have a lot of older people (think grandparents.) I know, you’re thinking “Oh wow, what’s the fun in that?” Well, at this point it’s not about fun. It’s about learning how to make (and keep) friends. When you go to the rock hound club, don’t try to hide your PDD. Let the grandparents in the club know that you are joining the club so you can practice social skills. They will be delighted to help you (and to teach you everything they know about rocks and making cabochons and slabbing and cutting geodes). A younger crowd, on the other hand, could be put off by this kind of personal information. Kids your age are usually still insecure themselves, so it could make them very uncomfortable to be seen associating with someone who says point-blank “I need help learning social skills.” They might be thinking “if so-and-so sees me hanging around this kid who needs help with social skills, what will so-and-so think about ME?”
4) go to all of the rock club meetings (and every hounding trip you can.) You will feel strange and out-of-place for the first few meetings. Expect that and accept it. But a club meeting is nothing more than a very structured social setting. The same things happen in the same order at the same place month after month, so once you learn the routine you don’t have to worry about trying to figure out what's going to happen next. And during the meeting people will talk to each other and make jokes and have little feuds and power struggles. You can observe how they interact with each other, what works and what doesn't, and – most important – you will get to know these people as individuals: what they like, if they have a short temper, if they like to bake blueberry muffins to bring to the meeting (that’s one of the perks of some club meetings, people bring tasty food), and the other people will get to know you. You will have the opportunity to practice being friends with them, and if you accidentally do or say something that is inappropriate, they aren’t going to stand up and walk away or say “I don’t want to play with you any more.” They can’t. They’re at a meeting. And the grandparents who know about your PDD will be there. They know how to smooth things over.
5) start volunteering to help out with the club’s activities. Help sell tickets at the gem and mineral show. Help set up and take down tables and chairs (grandparents really appreciate this.) Having some kind of specific task to do at an event makes the event much easier to get through, instead of just rattling around drifting from one corner to another and hanging on the edges of other people’s conversations, feeling weird. If you have an assigned task, you can say to yourself “all those people out there can see that I am part of this. I belong here.”
6) as you begin to feel more confident, start looking for more clubs you can join (but don’t quit the rock club). Get a part-time job. Volunteer to walk dogs at the animal shelter. The key is to find structured settings where you can practice being social, and get to know more people. And maybe along the way you will get to know someone your age who says “Hey, after this, let’s go hang out at the mall,” and the time you spend with that new friend will be less stressful because now you have things to talk about: “We went on this amazing rock hunt last summer,” “there’s a golden lab at the animal shelter I sooo want to take home with me, but we don’t have room for a big dog,” or “hey, want to come over to my place and play some video games?”