Stories where the characters learn to love others

It's been a while since I read it, but doesn't Bridges of Madison County have that kind of vibe?

Sorry, can't direct you to a specific book, but I think this idea is great and has a lot of potential.
I can think of a movie/ theatre musical though... let me google it, I think it is called Once... yep, here's the film link
http://en.wikipedia.org/wiki/Once_(film)

Your question reminds me of the movie Kissing Jessica Stein, although

(spoiler)

in that case I find it problematic that a same-sex is used as a learning experience for finding heterosexual happiness.

I think Hannah and her Sisters has themes similar to this as well.

Georgette Heyer's Regency, Sprig Muslin, is somewhat like that. The hero, Sir Gareth lost 'the love of his life', the dashing Clarissa seven years ago and Never Loved Again. But of course, he must marry and reproduce, so he proposes to the seemingly dull Lady Hester who's a Friend. She turns him down because she's secretly in love with him and it would just be all tragic to be married to a man you loved who didn't love you back. Along the way, Gareth meets up with the spunky and adorable young Amanda, who's a lot like a young Clarissa, and the assumption is that here's his love interest. He has to keep her out of scrapes and from accidentally ruining herself, so there are a lot of adventures and chasing about, with the upshot that Gareth realizes that Lady Hester is really the one for him. Sorry for the spoilers, but it's a really cute and funny read anyway.