Every negative experience leaves a negative mark on our mind.
When We talk about that to someone, they too would be influenced.
In the same way, when someone talks about others, it creates negativity in our minds too.
Although we did not have that negative experience, we tend to carry the unnecessary burden of negativity.
Stay positive, Speak positive, act positive and live positive. It takes a little while to practice but once done you will have a whole lot of happiness and tranquility.