If you are not grieving, you are not conscious. But if you are not rejoicing in the possibilities of how this could all change, then you are not looking through the filter of the greatest spiritual perspicacity.
Spiritual progress is like detoxification. Things have to come up in order to be released. Once we have asked to be healed, then our unhealed places are forced to the surface.
I am trying to be in that alchemical soup of human transformation. I am trying to process, reconcile, forgive, let go, and grieve, when necessary.
I think you have to grieve the loss of youth before you can claim the joy on the other side of it.