It's not selfish to take time for you. You need time to get refreshed, to be re-energized. You shouldn't be so busy you don't have time to be alone, time to laugh, time to exercise. You need recreation, you need these things that help you stay in balance.
See, when people are making a lot of withdrawals, you have to make sure you're putting in a lot of deposits. If you're giving all the time, and never filling back up, you're going to be depleted. You're good to others, why don't you be good to you? You're kind to others, be kind to you, be generous to you, be loving to you.