I feel for you, I have a small wall unit air conditioner in my apartment and the coolest I have been able to keep my place at is about 82. It hasn't been cooling down much at night either so it has been hard trying to get the apartment cooled down during the night.
What is funny or not so funny is a few months ago was talking with a coworker. They have a friend that works with the military in forecasting the weather and they were saying this is going to be one of the hottest summers that we have had in awhile. So far it has been proving to be true, trying to be thankful for the heat since the winters here can get pretty cold. Just wish I could get some sleep with out tossing and turning and sweating during the night.