I think it's normal to be happy for others. But that doesn't mean it doesn't leave us performing a little introspection with regards to our own lives.

Of which we think, why aren't I losing weight? Why aren't I getting married yet? Hmm why haven't I been able to go on a vacation yet? Oh because I might not be overly happy in my job, but I just saw my friend start what they think is their dream career.

You can be left questioning our own place when you are constantly being shown the highlights of others lives.