Can you really have fun, enjoy life, if you are sad?

You cannot paint a light color on a dark canvas and expect it to look the same as on the pot.
In this society, you have no right to be sad, or feel any negative emotion. So you paint layers and layers of fun on this dark canvas till the paint starts to crack and no one seems to be able to tell you why or help in a longlasting way.
But the moment you address the dark, you find your canvas was just full of dust. Why? Because you forgot about Your Self. You looked at your parents to tell you how to Be, and all they knew was to shake their own canvas over yours, sprinkling dust and bits of old paint, like their own parents did.

The bad is actually the good here, because no paint sticks on a dusty canvas. So it may take some time but you can peel away the layers of old paint till you reach the original canvas. Then you dust it, deep-clean the darkest parts, and start a new painting, of your own choosing.
This is when you will see how the dull colors you experienced are really vibrant.