Combine that with the fact that Derek is Meredith's superior and, was, oh yes, still married at the time. Over the period of the show the couple gets back together, breaks up, and has a whole lot of sex throughout.
Derek seems to always want more from the relationship than Meredith, who can't seem to commit to the idea of marriage. Granted, they are engaged now. But will Meredith's "dark, twisty" side allow the wedding to happen?
Robin Scherbatsky and Barney Stinson, How I Met Your Mother
One spends his life trying to sleep with as many women as possible, at all costs, and the other is a dedicated workaholic. Although Barney realizes he has feelings for Robin, he has no qualms with bedding other females despite being jealous when Robin and ex Ted Mosby begin to casually hook up. Read: Hooking Up: Liberation or Desperation?
When the two finally do reveal their feelings to one another, they decide to make out rather than figure out the whole "relationship situation."
Dennis Duffy and Liz Lemon, 30 Rock
Dennis, or "The Beeper King," has an on again, off again romance with Liz who is embarrasssed to be seen with him. Liz realizes Dennis isn’t good for her and tries her best to avoid him, but always gets sucked back in to the relationship whenever he comes around.
For his part, Dennis was convicted as an online sexual predator and slept with Liz's best friend, Jenna Maroney, while dating Liz. Poll: What Is The Best Revenge For A Cheating Boyfriend?
Hilarious? Yes. Healthy? No.
What television couple (past or present) do you think has the most unhealthy relationship?