Fighting your Demons
I've been doing a lot of thinking about this lately as I've been fighting some of my own. It's never too late, or pointless, to fight your demons. Even if you were on death row for something awful you had done, (though I admit this is an extreme example) it would behoove you to spend time wrestling them into submission.
It is likely you will never slay them. It is likely they will escape from time to time and wreak some havoc. This does not mean, however, that you shouldn't fight them with everything you've got. You will eat today – I imagine – despite knowing you will die someday, correct? Apply this logic to all things.