(Update 2015) Over the years I come back to this again and again when I need to be reminded.
It may seem shocking to say it but here it is. All feeling is bliss. All feeling.
“I feel depressed. That is not bliss.” Are you so sure? Is the essence of depression so very different from that of elation?
Depression is a point on a spectrum or continuum of affectivity. It is energy channelled in a certain way. It only needs a change of course and voila! the same energy is open and joyous and free. This is something about which I can personally speak with authority. How this can happen is another question, which I will not try to answer here, because there is no single answer for everyone. read the whole article here (by @AmitayusX )
________________________________________________________________
and another:
For most of us, we mistakenly think bliss means happiness. We cannot truly know bliss until we see it in our pain. — Tom Wootton