There's no yard stick to measure pain. Pain is Pain! Big or small! Stop acting like depression police. People don't need a reason to be sad! They really don't need to give you an answer why. Because, sometimes, they really don't know. We're all going through something. You're not in my head. You don't know what I'm thinking, You don't know what I'm going through and vice versa.
So, please, let's all respect feelings and boundaries. If someone wants to cry, leave them TF alone. Let them cry all they can. It helps a lot sometimes.