I'm not really sure what to tell you here. Your religious beliefs are something very personal which cannot or should not be forced upon you by anybody. However, alienating your father (or your father alienating you, as it would seem) can't be a good idea either for your future (and I AM talking about monetary circumstances). While parent<-->child relationships are important, finding a set of beliefs that suits your lifestyle is arguably more important. If Islam isn't your thing, I applaud you for standing up to see what else is out there.
As for being depressed, there isn't all that much you can do about the piling stress that's adding up. Try to occupy yourself with things that make you happy. Talk about your problems to others (like you're doing now). You could (although I know you already have) try reasoning with your father to find out why it's so important to him that you maintain your status as a Muslim. You could assure him that no matter what path of beliefs you choose, you will follow his rules and his moral code for the remainder of time that you're under his roof (as in, don't do anything that would make him cringe).
I dunno, that's my take on things anyway.
__________________
|