Went to the Happy Chef and danced around

For a while there I was stirring up the dregs, on the floor searching blindly for crumbs of Happy falling from the plates of those whose Happy overflowed. And suddenly all at once I'm served this big old giant plate of Happy with my name on it. No more sweeping up the crumbs. Now I'm invited to the Happy buffet. Please take a fresh plate every time!

Happy!Jess is back.
Happy!Jess takes life as it comes, and finds people endlessly interesting and hardly ever annoying.
Happy!Jess gives people the benefit of the doubt.
Happy!Jess loves to answer your questions and provide you with cheerful service and come up with creative solutions to your stickiest dilemmas.
Happy!Jess rolls with the punches.
Happy!Jess focuses her attention on the things that are going right, and they multiply. Things are looking up. And up and up and up.

It's not that I'm prancing around spitting sunshine exactly (though I do have that mode, it appears to be set on Hibernate), but there's been an unsubtle shift in my worldview. Where did this come from, and how do I get it back next time I need it? How much of this is a decision on my part, how much of it is circumstance, how much brain chemistry?

And how long will it last?