1) It's not cheating if you play footsy between stalls in an airport restroom.

2) It's not cheating if it lasts less than 2 minutes.

3) It's not cheating if you get a rusty trombone.

4) It's not cheating if you're practicing for a porno.

5) It's not cheating if you're in the military.

6) It's not cheating if you think of your husband while doing it.

7) It's not cheating if you do it out of pity.