Played by: Ted Danson and Kirstie Alley
But wait, wasn't Diane the love of Sam's life, the one that got away? We're not here to make a call on that, but we do know that Diane was a total drag. Shelly Long played the character so convincingly that it was almost impossible to imagine her in a sexual situation, which sucks for Sam.
Rebecca may not have been as good for the comedy on Cheers, but she was way more attractive than Diane. Highlights of their not-quite relationship included they time they had sex in Sam's office and another occasion when Rebecca tried to seduce him but was too drunk to get it done.