Why would you want to be anything else? I like being an INTP, if I want to be social I can, but in the end I typically need to recharge my batteries. I've gotten pretty good at being able to talk to random people and able to strike up a conversation. It by no means comes naturally, but I find the more you try the easier it gets.
The brain is a wonderful thing, if you do something enough times it becomes naturally embedded into you. If you genuinely want to change your behavior, and don't mentally block yourself, repetition will make it a lot easier.
Anyways, here are a couple of principles that have helped me with some of my friends:
1. Don't criticize, condemn, or complain.
-- How annoying are people that always whine and cut other people down? Almost everything I say has to be honest, so I try to find something positive to say. (This is a HARD one to do!)
2. Give honest, sincere appreciation.
-- If someone does something nice, or a good job on anything really (or even- not really, it just makes them feel better about themselves), TELL THEM!
3. Get the other person to eagerly want something.
-- This is more about getting someone excited about your ideas, give THEM a reason to want it. Don't you like it when something is relevant to you? Don't you hate it when people go off on some irrelevant banter or try to get you to do something that bears no interest to you?
4. Become genuinely interested in other people.
-- This one is the HARDEST one. People like it when you are genuinely interested and not just going through the motions, the trick is to ask questions to wade through the BS until you find a topic of interest that you can ask questions to learn things about.
-- This one is the EASIEST one, but it is easy to forget. Smile at people. Laughter is the best medicine and people like to see people smiling at them.
6. A person's name is the sweetest and most important sound in any language.
-- When you are unfamiliar with someone use their name with some regularity. It makes it easier to remember, and makes that person feel good that you know who they are. Don't you feel special when someone you hardly met remembers you?
7. Be a good listener. Encourage others to talk about themselves.
-- Again, if you learn to ask the right questions you can steer any conversation to a slew of interesting topics. I have found even the jockiest of guys, and skankiest of girls all have something about them that I find interesting. Also, people love themselves more than anything, get them talking and practice #4 and you're golden.
8. Talk in terms of the other person's interest.
-- This is easy once you get 4 and 7 down, just keep talking about what interests them and you can engage in conversation for hours.
9. Make the other person feel important - and do it sincerely.
-- Another good one, this makes people feel good about themselves. Hell, I love it when people make me feel like my ideas were useful and relevant.
I took these principles from Dale Carnegie's book, and found them to be very useful mini-guide to not being perceived as an asshole who doesn't talk to anybody. I have a little book I carry around with these principles in it, whenever I am feeling particularly anti I will whip it out and read a few lines to remind myself of where my head needs to stand. You need to GENUINELY want to do these though or your efforts will be fruitless.
I find we tend to be most internally stable, but our external qualities definitely need work...