I had some anxiety issues a few years ago, not necessarily like yours, I got lots of stomach problems so it lead to me getting nervous pretty much every time I left the house and consequently I would get really nauseous and stuff. It did a number on my life.
So yeah, it's not like what you're going through, but believe me when I say that with some work on your part you can get over it and you'll look back and be amazed on the progress you made on things that seems trivial to most people.
I agree with what others are saying: don't give a fuck. Most people don't give a fuck about you either and if they do... don't give a fuck about them. Other people don't think or notice things about us nearly as much as we think.
Baby steps are a good advice too, try to push yourself a little further every time, get a little out of your comfort zone, don't think too much and be yourself. It's OK if things don't go well, no big harm will come of it and you'll come out stronger. With time you'll get there without even noticing and all the control you had to force upon yourself will become automatic. Don't think "did I level up, am I better now?", whenever you do stuff, it will come naturally.
If nerves are really bad try meditating, nothing fancy or esoteric, just relax, get comfortable, close your eyes, breathe deeply and slowly and clear your mind. It helps to focus on just one thing like your breathing or maybe picturing a simple image. This helped me a lot.
There are great hypnosis therapies, but I don't know how easy it is to find a trustworthy doctor who does this instead of crackpot witch doctors, but if you can find a reliable one it could be a huge help.
Just remember that you don't need to be a social beast if you don't want to, you don't need to know 10 000 people, bang every chick you see and go to every party if you don't want to. Improve yourself little by little, don't stay in the house all the time, get into some activities, the friends will come and your problems will fade away.
Good luck!