I know I'm late to the party with this one, but I've finally started watching Nurse Jackie and I think it's wonderful.
If you suspend your disbelief about a few issues (certainly somethings would be impossible in the UK and they seem like the kinds of things that would be impossible in the US), it's a well-written and touching show. It's bleak, with dark comedy and a troubled protagonist. The titular Nurse Jackie is an RN with a drug problem, two men on the go (one is her husband, with whom she has two children) and dopey - if well-intentioned - student nurse in tow.
The show really picks up on a lot of things, such as the peculiarities of the relationship between doctors and nurses, the way that nurses are important for making people "better" in a more complete way than the doctors, how shift work can make your real life seem like just something that happens when you're not at work and how you can't save them all.
If you've worked as an RN, you'll feel well represented here, and probably enjoy the dark humour that drives so much of this show. I certainly do.