Sometimes reaching inside ourselves to be kind and positive shouldn't be misjudged as superficiality. Positivity despite tragedy comes from a deeper, ingrained desire to celebrate life.
We've all heard of the social masquerade whereby someone puts on a happy face when supposedly "deep down" they are sad. However, it is usually the saddest people who are the quickest to point fingers and shout, "Ah ha! I knew it! You're not that happy."
Sometimes positivity isn't always about hiding pain. Sometimes positivity is just that - positivity. When life gives you an opportunity to laugh, take it. When someone offers you a smile, return the favor. Doing so will allow you to feel better inside while knowing that sometimes, just sometimes, we laugh because there's laughter in our hearts, even if someone forgot to set out the milk.