Suppose at some point, you say to yourself, This is no good, I am living for myself and I am not happy. I’m being too hard on myself. I need to lighten up and give myself a break. So that’s what you do, but here’s the problem: You are still not happy, because while "self the servant" is off the hook, "self the boss" is no longer being served!
Living for yourself is an absolute nightmare. When you lay self out as the master, you end up being crushed as the servant. Then when you lighten up as the servant, you end up being shortchanged as the master. You cannot possibly win. And all around us is a culture that says, “Live for yourself!”
The Bible tells us that Jesus came into the world so that we can live another way: "For the love of Christ controls us, because we have concluded this: that one has died for all, therefore all have died; and he died for all, that those who live might no longer live for themselves but for him who for their sake died and was raised" (2 Cor. 5:14-15).
(You can read it at http://www.thegospelcoalition.org/article/the-inevitable-misery-of-living-for-yourself )