I believe the "you wouldn't cheat on your partner" implies some level of love, or like, or even tolerance. But a partner without those things? A partner where the relationship is based on keeping you from other loves you've known that have brought happiness? And offers fleeting rewards which require daily effort to keep. Never one day off. A lifetime with that judgemental partner who loves who you should be and who the partner thinks you should want to be, but will never accept who you were and where your heart once was. Anyone who can't imagine cheating on that partner has never felt passion. So maybe not good to use that one with dieting. Just sayin.