Electric Bill Help?!?!?!

Hi! I am a broke college student living in a suburban college town. I have one roommate and we share a 2-bed, 1 bath apartment. It is about 850 square feet and all electric.

We try to be fairly conservative with our energy use. We turn everything off (lights, tv, etc) if were not in the room. We only use the heat on rare occasion. We always leave it off at night and when we aren't home. We also leave it off during the day frequently (It's currently 57 degrees in here) and when we do turn on the heat we don't ever turn it above 65. The building was built in 1970, I am not sure exactly what kind of condition it is in but they completely redid the roof a few weeks ago. We have only lived here since December.

Anyway, I got my February electric bill today and it came out to $216! I haven't been paying bills very long but that seems like a lot. For comparison, my mom lives with my two sisters in a 3 bed, 2 bath 1200 square foot apartment and they blast the heat and leave the lights and tv on all night and pay about $85 a month.

I am just not sure where all that electricity is going! Any advice would be appreciated!