Article in English: If he calls you ugly or fat, never believe it. Remind yourself that he's just upset that you broke up and doesn't know how to deal with it maturely. You don't have to go out of your way to give him compliments, but don't be nasty in return if your ex-boyfriend says something mean to you. Keep your cool in these situations and show him that what he's doing isn't bothering you. This means being nice behind his back as well as to his face. Never try to get even and spread rumors about him. If you do things like this, you will be acting just as mean and immature as your ex, and you will probably make the tension between the two of you worse. If you and your ex-boyfriend have mutual friends and his mean behavior is making social interactions uncomfortable for you, let your friends know what's going on. They may be able to reason with your ex in a way that you would not be able to, or they may decide to stop inviting him to events as long as he continues to be mean to you.  Depending on the relationship that both you and your ex have with your friends, you may have to be willing to cut ties with some of them. Keep in mind that someone who encourages your ex to be mean to you is not really your friend at all. Talking to your friends about the situation will also give you a way to vent. Supportive friends will make you feel good about yourself, which will make it much easier to deal with your mean ex. If you ex's behavior gets serious enough that you feel like you are in danger, report him to an adult at your school or to the police. You should never have to live in fear of being harmed or harassed, so don't be shy about asking for help.

Summary in Indonesian:
Jangan membiarkan perilaku buruk mantan pacar mengganggu kehidupan Anda. Balaslah perilaku mantan pacar dengan kebaikan. Jadilah orang yang lebih baik. Berbicaralah dengan teman. Laporkan perilaku mantan pacar yang membahayakan diri Anda.