Just try to imagine:
You are being badmouthed.
By someone.
Either upfront or behind your back.
And you realized, this actually happened to you personally.
I think even a nice person would feel their blood boil once this happens to them.
Badmouthing is an act of saying bad things about a person, a thing or a situation. Criticizing is fine. It's actually helpful to the one you're criticizing but once it gets out of hand and it becomes a way to insult or degrade, you have to STOP there.
You see, doing this kind of thing is a way of being disloyal. You act nice, thoughtful and concerned but without that person, you reveal your hate and disgust to them.
I wonder what they get for being two-faced and insincere? Is it that hard to just be happy on other people's accomplishments? Why is there a need to ruin a person's image just to please oneself?
But here's what we have to do if we cannot just ignore them:
Imagine the smallest value of coin with two faces, that's how good-for-nothing they are. Let's not waste our energy on them, instead, let's prove them wrong.
Feel bad that they have nothing better to do so they resort to this. No way they are better than you when they bring you down which means they are below than you.
They messed with the wrong person. They messed with YOU. Show them how amazing you are. The gossips will never define you.
Badmouthing stinks and the one who badmouth stinks far worse.
Buti na lang hindi ikaw 'to!
Badmouthing is not good at all. You may ruin a lot by doing so. Friendship, trust, etc. They are at risk if you keep doing it.