Are You a Human Being or a Human Doing?
One of the challenges in creating work/life balance lies in the fact that it doesn't just happen. It must be created. And, once created, it must be protected. Zealously.
One of the fastest routes to balance is to block out some time for yourself every single week. Aim for at least an hour two or three times a week, but everyone has a personal minimum that needs to be maintained. What's this personal time for? Anything other than work. Remember that gym membership? This is when you can actually use it. Or get a massage, visit a museum, browse the bookstore, or have lunch with a friend. This is [a part of] the time that will make you a well-rounded, interesting human being rather than a worker-bee "human doing."
The tricky part lies in protecting this time. So often, we make commitments to ourselves and break them when something else comes up. The key to getting the benefit of these self-appointments is to regard them as being as important as an appointment you make with someone else. Yes, sometimes you will have to cancel them. But if you find yourself canceling on more than a rare occasion, you aren't really making an appointment; rather, you're making a plan that will fold if anything better comes up, or if someone else asks you to do something work-related. Getting the benefit requires making the commitment.
Pull out your calendar, your PDA, whatever you use to keep track of your time and schedule some time for yourself. RIGHT NOW. Waiting until you know what demands may be coming your way won't make it easier to do, it'll make it less likely. Although spending time away from your work-related commitments may feel strange in the beginning, commit to trying it for six weeks and see what happens. There's every likelihood that you'll feel more relaxed and find renewed energy for your work.