GS vs STA: Unexpected Love

I had an interesting inquiry for recommendations from Jen, and I've been struggling with how to title it – it's not quite “last chance” at love, but it's more than “surprise, you have FEELINGS.” Jen writes: 

I am looking for a book I've never read and don't know exists. I am totally into the idea of lonely people finding each other. Either or both are lonely. And the writer does an excellent job of making the reader feel the loneliness and bleakness of their future.

Oh, and the romance when they find each other has to be pretty fucking hot. Any recommendations?

I asked for clarification, and queried as to whether Jen was “looking for stories wherein the heroine or hero has given up on ever finding anyone, and WHOOMP, there s/he is” and she replied, “Yes…but I would like to allow flexibility around the definition so I might have many books to look into. But, yes, essentially I would like to read about one or both parties either giving up or never having hope to begin with of having a true lifelong partnership love…but they find it.”

Well, darn. I kinda want to read that now, too. 

The first book that I thought of was my favorite of the “Immortals After Dark” series, Dark Needs at Night's Edge by Kresley Cole ( A | BN | K | S | iB ). The hero is a tortured vampire held prisoner by his brothers, and the heroine is a ghost with a fabulous sense of humor.

That might fit Jen's reading curiosity – but I know you have more suggestions. Which romances do you recommend featuring characters who suffer from bleak loneliness but then find happiness?