I think non-attachment, like meditation, is a practice. It is an ideal that is never done but continuously train ourselves to do. And so, we should stop using it as a catchphrase to tell people to stop being too attached at something or someone especially if they just lost it. Give them a break! They are trying their best. Also, perhaps a true practice of non-attachment involves being not too attached to non-attachment itself and allowing ourselves to face the full range of human emotion and experience by commiting ourselves fully to someone or something and letting ourselves “suffer” from their loss.