I have a lifelong issue with stress and anxiety, to the point of actually having been diagnosed with Panic-Anxiety Disorder. I'm still quite susceptible to longterm stress, but I can tell you that meditation has been extremely helpful with this. There is scientific evidence that it actually physically alters parts of the brain in positive ways, but it also gives you a way to step outside your stress and anxiety for a little while, and that little "breather" can be extremely refreshing, I've found.

So, meditation, regularly and frequently, even if it's only for a few minutes at a time. Keep at it long enough, and it gets easier and you'll definitely feel the benefits.