Do Work!

Honest question: Why is it so hard to stick with something like working out or eating better? I know I'll feel better and look better, so why is it so hard? Especially the eating better. It's not really that much more work, it's just picking different things and a tad less convenient.
It's such an interesting thing, I think, that our nature is so very self-destructive. We are automatically opposed to things that make us feel better in the long run because it's hard in the short run...especially if it happens to be a long run we're trying to go on! (Sorry, couldn't help it.)
I know that, if I start being regular in things such as eating well and exercise eventually my body will start to crave these things instead of a double chocolate doughnut. (But, honestly...double chocolate!) It's the getting over that hump of the bad cravings that is so very hard.
My goal for this year is to get off my butt and do things. This month is yoga, next month (in theory) is running. I'm also trying to be more intentional in my eating and not just stuffing food in my face. What are your fitness goals for the year?