Found out my roomate's GF used to be a mega-ho

[dustyn]

What Dom said - this is none of your business at all. You are more likely to be seen as the [censored] here by both Joe and Maria than as some sort of "righteous truthteller." The odds of you seriously hurting two friendships are high because you are out spewing rumors about your roomates GF's sexual history. Just STFU and let them deal with their own relationship.