"(our studies suggest that) when evaluating outcomes in isolation, people tend to be more concerned with interpersonal comparison of outcomes than with maximizing personal outcomes." 
"(…) these judgments appear to be biased in a self-serving manner and to respond to factors that are difficult to justify on normative grounds. Our own recent research has focused on one particular dramatic example - the tendency for relative comparisons to receive much greater weight in one-at-a-time evaluation than in comparative choice." 
Comparisons are inevitable. We all compare, whether we want to admit it or not, so if we all do it and we can't help it, then it is not a problem. The problem is if you let it affect you.
When we compare we only see the good on the other part and the bad part in us. It's skewed. It's a game designed to lose.
It will happen, because we can't help it. But it makes no difference, it doesn't mean anything to anyone. It's just a bug in your brain. Keep going.