I have to admit that I do this as well. Not so much as I used to but I still do it. I think the best way to deal with it is to pick things that you're good at and nurture them. If you're into sports, join a team, if you're not on one already. Write, if you're a writer. Make art, if you're an artist. And when you're around other people, it might not be so easy. But with each time you slip up and fall back into the behavior, try to remind yourself that you want to change, that you are changing, that a different life is yours to be had. See if that makes a difference. It's really hard to change ingrained behaviors, especially ones we've had for a long time. Patience (that nasty word).