This is what I have decided.
When I am busy, I am happy. When I have nothing to do but eat cereal and jump on my trampoline for weeks on end then I become sad. Not that I don't enjoy those two activities, but when those are all you do it can leave lots of time to over think every detail of your life. Which is not good.
That is why I have been happy for the past few weeks. I actually have things to do, places to be, and people to see. I have also come to realize that when I think about all the little things that make me happy instead of the things that don't, I am much more likely to have a swell day. And a swell day is something I have been enjoying quite often.