I try to give myself a break, do things like read a fun book, eat healthy food, and like you said, work out consistently. If it gets really bad you might have to cut back on one of the things contributing to it, or it might cost you more in the long run.
Last fall hit me pretty bad. I was working full-time on nights, commuting 2 hrs one way for grad school, volunteering, taking a pretty hefty course load, along with other stuff. I'd been on nights for 5 years and despite being a night owl, it seemed to be the biggest problem. I started looking for a different position even though it meant I'd have to slow down on the school side. I wound up getting a promotion and moved to days. I had to cut back on school spring semester, but I feel like a whole new person compared to last fall and I'm doing well across the board now.