Thank you so much for your comments and advice. I don't really have a ton of girlfriends, because the girl:guy ratio in Blacksburg is like 1:15...which is normally great but not when I have any kind of drama going on.
Since getting your comments, I have been officially invited (via facebook) to the housewarming party. However, I am moving on Sunday, and it was up in the air as to whether my boyfriend could come down for the weekend to help or not. He has since decided to come, and he's getting here Friday. So, the decision was really made for me. Phew.
However, facebookw has intimated that there will be a large reunion around Christmas, when all of us will, in theory, be around. So now I have a couple of months to consider what I plan to do.
In honor of my sister, I will probably do what she always does, and take the high road. Whether that means going to this reunion and making nice, or just politely stepping away from the situation, I don't know.
But I'm not as worried about it now, mostly because you all said the same things, and they really made me feel better. Thank you so much (c: