It is a very complicated question. What is your defination of cheating in the first place ? What constitues a cheating ? Having sex only with your partner, husband/wife, lover, BF/GF yet being mentally/emotionally/psychologically intimate with someone else. Does it (or NOT) fit into the defination of cheating ? Only we all can harmonize many diverse definations of cheating we then can proceed to determine if someone is cheating or not. Wether someone who has cheated once will go on cheating again and again is far greater challange to find any conclusive answers.