Start building up your web presence. Open another account, be it Facebook, google+, instagram, whatever. Post pictures of urban life or wilderness travels or night life in your town. Go to a cafe, order an elaborate looking meal, take a picture of it, or, make one at home and take a photograph. Make short status updates that reflect your current stage in life as positively as possible. Share your literary and arts interests if you have them. Basically, present yourself as an urbane and sophisticated person. When you have built that facade, you can send friends requests to your former roomies. They will see that your past vulnerabilities (lack of sophisticated veneer) are now a thing of the past, and feel powerless to resume hurting you.

That's my reaction to reading your account and if it makes sense to you, implement it slowly, without impulsivity.