I'm not pro at being an always-happy or easy-to-get-along-with person, but I remember some good quotes I've heard that always help.
Damn it I probably can't remember them exactly, but they go something like this:
- A boat only floats when there's no water inside. In the same way, problems only affect happiness when they're taken onboard.
- It is not the size of our problems, but the lack of spirit, that makes us complain.
On a side note, I find that just getting out of the house and doing something fun and physical outside helps a lot when things are miserable. It gets the blood flowing again after sitting down at the computer all day.