Yeah, pretty much everyone can benefit from some long term therapy, I would say--but if you're suffering from PTSD or anything deeply uprooting, it can be hugely helpful for helping oneself to move on.
Pushing away people... I have lots of conflicting feelings about this. The first kind of pushing away is like this: on the one hand, you gotta get the poisonous influences out of your life. Maybe the person can't handle you with such intensity in your life, maybe they really are just hateful and you never knew it till now, when you struggled so much. But they've gotta go--even if, on the other hand, it makes you sad and lonely. Then there's the question of support. While often having superficial relationships is better than leaving yourself alone to your anxiety, it's not what you NEED and it's not going to help you heal. And if those relationships are making you feel bad, then they're not worth it. Finally, there's the fact of self-isolation around trauma. That happens a lot. It's easier to feel more alone, more depressed, and to push more people away when you're already dealing with so much AND it is true that many you do know don't understand what you're going through. Having some true support--even if it's just one person who will listen closely and who you can talk to anytime--is a huge help, makes it all easier to deal with. Maybe there's some kind of group for that where you're at? I don't know where you're living so I dunno what's out there, probably wouldn't really anyway. But those are my thoughts on the subject...