I love all of this except “Happiness is a choice.” The saying has become so trite.
Happiness is not a choice when you are grieving, or very ill, or in dire circumstances.
Give yourself permission to feel grief, to feel sadness. We all go through these things. Try to remind yourself that circumstances can change and life can get better. I think that might be better advise.
But to pretend to be happy ALL the time is just phony.