People who always try to cheer you up, who always put a smile on their face, no matter what life has to offer them, who are always there to support you; these are really lonely and sad people. They know what it is to be completely broken and alone. They know how it feels when no one is there to wipe your tears. So, they try their best to make you feel loved and heard. Not only this, all their hope to find a friend( a true one) lies in this act. They think that if they'll understand people, others may reciprocate it and try to understand them and make them happy as well.
But sadly this doesn't happen and these broken souls are never mended. But this doesn't stop them from faking happiness to make you smile. Contentment of not letting others fall is also enough for them.