I totally get the struggle. Some points that may help:

• Atheism and theism should be seen as matters of degree. No reasonable atheist should be 100% certain there is no god (after all it's possible even for the Flying Spaghetti Monster to exist), and no reasonable theist should be 100% there is a god (though many will say they are).
• "Atheism" has lots of negative connotations, especially for someone growing up in a religious tradition. It can be hard to accept the label for these reasons. I called myself an "agnostic" for years when I would have put the probability of God's existence at about 1%. By any reasonable measure that's atheism! It sounds to me like you're already what I would count as an atheist. But this does not mean you're amoral, or think the world is depressing and bleak. It just means you think, on balance, there probably aren't any gods out there.
• Remember just about everyone denies the existence of some gods. The (consistent) Christian denies that there is Zeus, and so on. As one guy put it, you're just an atheist about one more god than the Christians are.