My suggestions are based on my own experience to those ppl who very sincerely loved and got into some relationship and got cheated upon . Some ppl mighthave a disagreeing over my approach however I found this approach appropriate, very effective, very memorable for me (no doubt, for the cheater as well) and of course veryentertaining as well..ha ha ha. Anyway if you are in one of such situations, you must realize that you have been systematically intruded upon and you must take a systematic approach to deal with it. The bottom line will be "Trade fire for fire". Once you discover that the girl is cheating on you, stay calm and don?t over-react. Don?t ever let her know that you have found out that fact. Even the slightest hint to her will ruin your case. In fact it can be a funny and very entertaining matter while you teach such girls a very good lesson. Be patient, cool down, and take a very methodical and systemic approach. Make an extensive and complex plan of action and strategy by doing some study, research and analysis on her. The process of teaching a lesson starts as soon as you begin to fall in relationship with someone who seems to be very eager to be in relationship with you but does not posses credibility, trust, reliability, honesty, self-discipline etc or something about her that gives you a fishy smell. Anyway, when you discover that she has been cheating on you, try to make her believe that you are in love with her more than ever by doing something special to her for example buying her a special gift by looking out for an excuse such as birthday, X-Mas etc.(in my case I made an excuse of her birthday for buying her a gift). You can try out some other things depending on your case. Totally convince her that you deeply her. Introduce some girls you know of to the guy (for whom your cheater girl is falling for). By doing that you have built a prospect for that guy to cheat on her as well. When When this guy begins to cheat on the girl. The guy loses the moral ground, because the guy has cheated on her as well. Now, it is your time to move in tell him that she has been cheating on this guy as well a yourself. Now it?s time to take a drastic and dramatic move on this cheater girl. Ditch the cheater girl. Very calmly and without showing any feeling of anger or distrust or avenge, tell her that you would have loved to continue this relationship but you can?t due to some personal reasons. Don?t ever tell her that you are ditching her because she cheated on you. If you tell her, you will lose another possible opportunity to humiliate her character. Your mission is complete. You will see some really entertaining and funny scenes about her down the road. Keep laughing and enjoy the whole thing ?..chao?