"Our mouths were filled with laughter, our tongues with songs of joy. Then it was said among the nations, “The Lord has done great things for them.” The Lord has done great things for us, and we are filled with joy" Ps. 126:2-3.
So much of conversations are "what's wrong" with the world, and yes even what's not right, or missing, or unfair in our life. Happiness isn't a guarantee in this world, nor is societies definition of prosperity. If we would focus less on what we don't have and more on what we do have we would indeed be content and thankful. God has and does bless us with all we need. He loves us and cares for us and about us.
Being thankful and smiling is good for our spirit and health and honors God. Others may then see there must be something you posses that lends to such thankfulness, smiles and laughter.