I love this post! It was good to hear in my life right now as I am learning how to be. This is all absolutely true. The only way to happiness is through experiencing the unhappiness. First, I think this act of experiencing can possibly even be had in the imagination, and achieve the same goals as ones had in real life. Second, I agree that in order to achieve happiness we must learn from the unhappiness, but I would consider intensifying that maybe even to the point of experiencing them as one; so that they are no longer separate and therefore contentment is realized because you could need neither...there is no neither...and they are both merely your life experience.
These are two things I've toyed with for some time now, and I'd like to hear your thoughts:)