Marvin Gaye / When Did I Stop Loving You / Here, My Dear:
Anything from this album -- written as a fuck-you to his ex-wife for alimony royalties -- would probably push your point. But this last, 47-second track (a reprise of an earlier song) sums everything you want to say succinctly, and the sheer afterthought quality of the song just underscores it.

Jeff Buckley / Last Goodbye / Grace:
The soaring nature of this song will enhance your feeling of freedom, and save you the trouble of writing a note.

Fonda / The Sun Keeps Shining On Me / The Strange and the Familiar:
In case he keeps asking, "Why"?

Spiritualized / Broken Heart / Ladies and Gentlemen, We Are Floating in Space:
This'll numb him when she has to get out the door fast.

Tori Amos / Crucify / Little Earthquakes:
A compliment and a summation of the problem in the same sentence: "Just because you make me come doesn't make you Jesus."

Patti LaBelle / Lady Marmalade / Nightbirds:
The song that begs the question (Voulez-vous coucher avec moi ce soir?) that got the whole mess started. And maybe he'll be too busy dancing to notice that she's packing.

Radiohead / Fake Plastic Trees / The Bends:
It'll give him an excuse to cry, if he's having a hard time faking it. Let Thom Yorke do the work of telling her ex he's plastic -- or, er, polystyrene.

Slick Rick / Treat Her Like a Prostitute / The Great Adventures of Slick Rick:
An explanation of his relationship aesthetic (and the reason why Sara had to go).

Pulp / Have You Seen Her Lately? / His n' Hers:
This is what all her friends told her, and she ignored them.

Bob Dylan / Sara / Desire:
A sweet, melancholic ballad written for his soon-to-be-ex-wife. The connection should be inspiring.

George Clinton / Atomic Dog / Computer Games:
She'll need something more upbeat to balance out the list. And "Atomic Dog" has a nicer ring to it than "world-class bitch"!

Richard Pryor / When Your Woman Leaves You / ...Is It Something I Said?:
Richard Pryor can give some great advice on broken relationships, and how to mend them. Any listener should pay close attention to his "psychology bag".