Hmm, I have different feelings about this one.
I haven't made up my mind completely, but I don't think happiness should be a goal, or even a measurement of anything. Happiness is a side-effect which you have little or no control over.
Aim for value, something that is important to you. (Like caring for someone, writing a book, etc...). If you do that, you can carry any suffering that comes to you.
At least, that's what I recently read in Viktor Frankl's book Man's Search for Meaning. He survived concentration camps and after being released continued his work as a psychotherapist, using his experience that focussing on value instead of happiness/justice, is what makes people survive.
So, I agree with many of the things you write, but the sentiment of 'choosing your happiness' is something I don't share. Or perhaps I misunderstood you?
It's ironic how often this search for "happiness" turns out to be clutter that actually keeps us from finding the very thing we're looking for.
I think a lot of people-- as you hint at-- find happiness as a side effect of being engaged in something they have a passion for; something that gives their life purpose and meaning. Although it has moments of frustration and even anger, my wife finds happiness in "helping people" through being a counselor, life coach and minister.
When I speak of "choosing happiness" I suppose am am really more oriented towards making positive choices; having a positive focus. When it rains, do we become grumpy because we get wet when we go outside, or do we choose to be grateful because rain brings life and makes things green? I've found that an orientation towards positivity often can become a foundation for happiness...
Someone once told me that when you start out having a bad day you should wear nicer and brighter clothes than you usually do. It makes a difference in how you see yourself and in how others treat you. It makes your day better (of course you have to be willing to be happy too).
It made me realize that it can be a chore, uncomfortable, and inconvenient to make positive choices but those things that you don't want to do can put you on the right road for the things you really want. Being happy in the long-term can be really annoying at the current time .
great information so happiness' is something .