What do you think of me squandering my parents' college money?
That's awful. Is there any particular reason you want to waste their money?
They think my sister is better than me.
I understand that it would be frustrating if you think your parents are playing favorites, but you shouldn't waste their hard earned money. They worked and saved to afford to be able to send you to college. You should be grateful for that and work hard in school so their money was worthwhile.
FUCK THEM! I'm taking their money and going out every night.
Don't be so angry at them. Instead of wasting their money talk to them about how you feel. That will make you feel better rather than spending money on things you don't want or need.