You don’t tell someone to master their emotions when they are going through an emotional crisis because that statement feels like telling them to move a mountain. Just hear them out and make a kind gesture, could be a hug, a pep talk, a joke or invite them to a more lively space so that they can have a change from the currently environment. This act will mean a-lot to them and chances are high that they will feel better. It’s way better than preaching the gospel of self worth and dignity: it doesn’t help.