my battery dies overnight
It could be that you have something plugged into your cigarette outlet, or you have an electrical short somewhere. I would recommend taking it to your mechanic and have them run a test for you. They should be able to locate the problem.
There could be a drain, like the above answer suggests, or it could just be a bad battery, a bad connection, or a bad alternator- how old is the battery? does it sit outside? did it get REAL cold last night? look at the battery cables- are they corroded?
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