Good question… I just recently made a change in my schedule and reduced some of my hours for this very reason. (I do personal training and teach fitness classes). I found I was taking care of everyone else and helping them with their goals, but on the way to neglecting myself.
Now that I have added a day off to my schedule, I feel much better. I have more energy, more time with my family, and more time to take care of myself.
I had to learn to say no to some things, but I am much better for it.