"I don't believe; I know." -Carl Jung
I could talk your ear off about why, undoubtedly putting you straight to sleep on your keyboard, but you know who sums up my feelings perfectly and much more eloquently? C.S. Lewis. A former athiest, he was someone whose faith was happily married to reason, and I find his talks on God quite lucid. (One quote of his I like: "I didn’t go to religion to make me happy. I always knew a bottle of Port would do that. If you want a religion to make you feel really comfortable, I certainly don’t recommend Christianity.") If you need a good place to start on why you might rationally consider belief, I cheerfully recommend his book, "Mere Christianity."
There are also some highly regarded scientists and other cerebral folk who've written books on how they've come to believe in some higher being because
of their scientific work and how the universe is designed, etc., etc., and I can look those up for you (or anyone else reading this) if interested. (Their names, of course, escape me at the moment, because guys like Richard Dawkins get more press.)
All that said, however... as much as I depend on reason to help me understand (as best a mortal can) my place in the universe, and the Big Guy's, too, I also allow for sacred mystery. One can either be insulted by the idea that one will never, in this realm, know or understand everything there is to know about God, or one can embrace it. I choose to embrace it. Others will think me a fool for saying that, I'm sure, and say I shouldn't believe in anything that can't be proven by our human scientific methods... but that is the nature of faith, is it not? There is something inside of me that pulls me inexorably toward my Abba, and all the Dawkins in the world cannot change that. Sorry, Richard.
I love God, even when all His ineffability drives me nuts. I've come to see Him not as some angry or distant Thing, but as an actual Personality. And so if you ask Him to help you find Him and you mean it (even if the prayer you croak out feels weird or like you're praying into a dead telephone), He will respond. Might not be right away (His timing is also a sacred mystery, it seems like), but He will. So try to stay open. He respects our choices (even when they're wrong) and will not strong-arm you into believing. Wouldn't it be easier if He did? (Of course, that still doesn't mean we'd all be Mother Teresas or whatever. Satan believes in God, too, and look what he's up to.