If you have to ask, you dont. You will either trust the person again and their actions alone will dictate this, or you wont. Odds are they will cheat again. Just the odds. So, its your choice. Ive cheated, theres nothing the other person could have done. And id have cheated again on that person. But i finally grew up.
So, you really dont get past it most of the time. Sorry youre going through it.