the people actually are jealous about others like why are they more happy so to show that they are also happy (when they are actually not) they do it!! 😂

why would any one went to post a sad or bad moment of their life and if someone does also then people will say they are doing it for sympathy

You've given the answer yourself. To show off.. I find such people very shallow because in reality they aren't as happy as they seem on their stupid profiles.

to spread happiness.. simple. u should be happy for everyone