Superbowl party problems?

The only thing I can tell you is to make peace with this girl if you can. Its quite obvious that your Mother will not give in to your demands. Sometimes you need to be the one to approach the person who is bothering you and ask why they are being mean. You said that you used to be friends with this person. Why not try to find out why things went sour between you two? Instead of allowing someone to make you miserable, try reaching out by overing an olive branch. In other words, try to make amends. Find out from the person what you did, (if you did anything) and see if you can rectify the friendship. If not, then I suggest you steer clear from her during the party and find other people to mingle with. But I suggest trying to figure out why she dislikes you so much, and state your case as far as how you feel she is treating you.