I have found that, at work, if you just stop doing whatever it was that people didnt like, they will forget your past and take you as you are now. Unlike my mother, who would constantly bring up the past and never let me forget it! So i found work to be more accepting of me in that way,

So its not a matter of "fixing" relationships or apologizing to everyone, it will be about being able to focus on the work at hand, and for you yourself to accept that you are part of the team.

I think some sort of group therapy or other group participation, a running or a knitting club, whatever you like, volunteering somewhere for the holidays, might give you the social training and support you need, and help prove to your boss you are changing.