Was it the happiest day of our lives? Probably not, if only because the truly happy days tend not to involve so much organisation, are rarely so public or so expensive. The happy ones sneak up, unexpected.
Perhaps grief is as much regret for what we have never had, as sorrow for what we have lost.
"I love you" is an interesting phrase, in that apparently small alterations–taking away the I, adding a word like lots or loads–render it meaningless.
Emotional intelligence, the perfect oxymoron!
From an evolutionary point of view, most emotions - fear, desire, anger - serve some practical purpose, but nostalgia is a useless, futile thing because it is a longing for something that is permanently lost.
The problem with telling people that they can do anything they want to do is that it is objectively, factually inaccurate. Otherwise the whole world would just be ballet dancers and pop stars.