Worry. How do you combat it? Well, first of all you need to figure out what "worry" is. Worry the constant meditation on a situation that doesn't reach a solution.
In short, worry is praying to yourself.
Trying to be constantly aware of a situation and it's outcomes is very hard for a person who is not omniscient, omnipotent or omnipresent. When you try, you become omni-annoying.
Praying to yourself is praying to a being that has no control over a situation. When Jesus said "Do not worry" in Matthew 6, he isn't making a light statement.
"But God didn't come through last time!" Oh really? Well, let me ask you this: Did you even let Him? or did the Credit Card god get more attention? or were you placing your faith in something man-made first. First give praise to God for being God and then let him decide what he wants to show you in his time.