Originally Posted by
RecklessEric 
AA would say this is the wrong reason to quit, that "You have to do it for yourself". But the vast majority are happier when with the people we love. So it is possible to do it for yourself and for somebody else simultaneously.
That's a great point.
If seeing another person happy and cared for makes you happy, then it's part of your happiness. If taking care of them yourself makes you happy, that is part of your happiness.
Incidentally, you could pull this from AA too, since AA is both what is reflected in the official literature (which says selfishness is the problem), and the commonly stated pronouncements of its members ("you have to do it for yourself", or "this is a selfish program").
Someone brought up my mention of psychological egoism earlier, and I think it might've been misunderstood, so I want to clarify it now in case anyone doesn't know what that is. Psychological egoism is not a prescription to be selfish - it is a
description of motivation which says that we are all motivated to act by self-interest (whether we realize it or not, or like it or not). It doesn't mean the actions we choose will necessarily objectively be in our self-interest - just that at root they are motivated by a pursuit of self-interest. It's nearly identical to the philosophy of the freedom model. We take as our starting point the idea that everyone is pursuing happiness in everything we do.