Most Helpful Guy
Ever hear the saying that the best revenge is living well?
That statement hold a lot of validity. Cheating is wrong, and you have been wronged seeing as it happened to you. And it is only natural to want to get him back. But the time and effort that you have to put into getting this revenge is simply not worth it in the big picture. It is a short term high and will not serve the best purpose here.
The best thing (IMO) here is for you to realize that this person is simply not worth your time and get over it. The fact that you would even put effort into getting revenge on him will just give him more satisfaction seeing as you are making an effort to do so, if that makes sense.
Try and find comfort in the fact that his decisions will surely do their own revenge for you as they will affect him on his path in life. Let the karma happen on it's own, because it will. In the meantime get on with your life and find someone who has more respect for you. This is ultimately the best thing you can do.