I only read a few of the posts, but I feel I should comment here because I am an INTP that has suceeded in becoming sociable. I was the most shy person you ever met until like age 17. Now I have recently been described by 2 different people as a "social butterfly"
step 1: start with appearance. I know, we don't care about appearance, but really put in some effort and become the most attractive version of yourself, this shows self confidence and makes people respond better to you and improves your self esteem and all sorts of good things all in a positive feedback loop. START WITH YOUR APPEARANCE. Sounds like bulshit, it works.
step 2: the next key is in understanding Ne well enough to capitolize on it's socialising capabilities. crazyness, whimsicalness, fun (stupid) ideas. alcohol helps.
step 3: alcohol. become an alcoholic (I'm exagerating of course), alcohol makes you 10X more awesome in social situations. don't go clubbing, you can't cope and you hate it. go to house parties. house parties are great.
step 4: finding people that you deeply connect with is hard, stop trying. instead, make millions of superficial connections and stay in contact with them. find people you can tolerate and make a point of doing things with them. drinks or rock climbing or bowling or whatever, you don't have to enjoy the time spent with them, you just have to pretend to enjoy it and stick ur finger in a lot of pies (so to speak). lots of connections with friends means lots of social opportunities.
step 5: always say yes. if a friend invites you out and you say no, they might try once more, maaaaybe twice if they like you. after that if you still say no, they don't bother contacting you again.
step 6: learn to do that Fe stuff. fake it till you make it. pretend to care about people, lie to urself even. lie to urself and tell yourself that you care about ur friends mums operation, because friends like you alot more ALOT MORE when you make even tiiiny gestures that you give a shit about them as a person because MOST PEOPLE IN THIS WORLD don't care about other peoples lives. BE the guy who DOES care and people will like you alot.
conclusion or something: I am definatly an INTP and I was DEFINATLY shy as hellllll. more shy than anyone that I knew. and now I am absolutly comfortable socialising and I have lot's of friends. take my advice. it works (if I conveyed my experience accuratly). if you try it and it's not working, feel free to message me, I'd love you help you improve your socializing skills (awwww sheeit there's that Fe caring about you)