Hi Stacky,
I can't wrap my mind around the idea of God either, but believe it or not, that's a good thing. A being big and transcendent enough to have created all this, including you and me, is going to be beyond my finite comprehension. But, regardless of what the science-only types try to tell us, all this had to get here somehow. One of the basic rules of physics is that, from nothing, you get nothing. So the universe can't just have spontaneously appeared out of nothing. We can see mechanisms, like the Big Bang and all that, but none of it tells us where the original singularity came from or anything else. The only explanation is that somebody or something put it there. Where did that being come from? As I said, it doesn't matter. We're answerable to our creator, and that's all. That's what counts.
Beyond that, we really can't give you much. I understand why you're having a problem. But as Fr. Chuck said, the best thing to do is put aside any preconceived notions of what you think God should be like, and start looking around to understand as much as you can about what he/she/it is like. Too often we're tempted to create God in our own image, so to speak; "a loving God wouldn't do this, that or the other thing," that sort of thing. "Why doesn't God do something about X?" Answer: I don't know. He's beyond my comprehension. But he has to exist; there's no way around it. That gives you a starting point on which to build a viable faith that can hold up under scrutiny.
And no, you're not a horrible person. You're not even a bad person. You're a normal person just like the rest of us. Take comfort in that.
Hope this helps.