Bit of a two tier thread this one, no? Theres the 'sober music' that's to encourage an air of optimism such as the ilk thats played at a particularly local methadone clinic every time enter that does my fucking head in, ie 'Things WIll Only Get Better' by Take That, 'The Drugs Dont Work' by The Verve etc...
Or do you refer to those songs you listen to while sober and not under any substance...? If in the case of the latter - most of Tom Waits' back catalogue, likewise Leonard Cohens, Philip Glass, Yann Tiersen and...well, soundtracks in general, really.
I've possbly picked that up wrong.