When someone says something negative to anyone it does hurt their feelings, but wise people know that they are going to go through their lifetime where most people will like them, but a few will not. Sometimes people who do not like another are either jealous; possible bullies or, they are just troublemakers or miserable human beings. Just move on and do not worry about it. This too shall pass and if you do not let this get you down so it chips away at your confidence level there will be many people in your future that will truly like you. When this type of thing happens say to yourself 'So, who is this person .. at the end of the day they aren't much and I'm not going to let it ruin my day.' People who talk behind another's back has a poor character and one day that person who said something negative to you will get the same treatment back.
