Humans always tend to fall into the trap of discussing others. This is an instinctive feature which makes them talk about others unabashedly and invariably interfere in people's matters. Ironically, the same instinct drives them to lose control when they hear the other person does it.
Solution : the best we can do is just don't get bothered by what they have got to say about us and stay as much away from their negativity as much we can. Life is ultimately about absorbing the positivity from around and neglecting the negativity.
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