Yes to 'Women who run with the wolves'! Best self help book of all time, no worse for being written unconventionally.
'Women who love too much' by Robin Norwood: dogmatic and victim blamey, but until I found it I thought pretty much everyone else in the world had great relationships or at least functioning ones.
'The last days of Pompeii' by Lord Lytton! First 'adult' book that came into my sticky little hands aged 10 or 11, after I'd devoured the whole of the school library minus the interminable Tolkien, but wasn't allowed to touch my parent's library of three or four Jilly Cooper type airport novels. Bulwer Lytton had a baneful effect on my literary style for years to come. 
The Rubaiyat translated by Edward Fitzgerald. All the imagery of death and decay and beautiful futility was balm to my 13 year old soul. :)
The plays of Aristophanes in the Penguin Classics translations, which weirdly enough had been donated to the library of my very rough ex secondary modern. What subversive indecency and irreverence for authority lay between those demure beige covers! I did a classics degree some years later, not before changing schools though.
'Deschooling society' by Ivan Illich. Kind of summed up the way I felt about my schooling which had ended only a couple of years before. Nice to know I wasn't the only one.
'Reinventing collapse' by Dmitry Orlov (a conspiracy theorist whose subsequent writings are mostly drivel, but this one's based on real experience and is right on the money.) Holy sh*t, the world's ending and I'm not even on the property ladder yet! Cue four years of frantic saving and researching the hell out of bugout locations and all things survival related. See also 'The road' by Cormac McCarthy (silly affected style notwithstanding) 'The grapes of wrath' by John Steinbeck and 'The road to Wigan Pier' by that peerless pamphleteer and hopeless novelist Mr Orwell.
'The Melanie Brown stories' by Pamela Oldfield: the first books I ever read to myself circa 1980, after my knackered mum said they were too long for her to read to me!
Proust's 'Jean Santeuil' and his magnum opus which I read in English as 'Remembrance of things past' (?) as I hadn't got round to learning French properly yet. Practically the only novel that didn't make me think 'Meh, was that it?' - in spite of being literally a foot long. OK, there were others, but I tend to keep them in case the kids want to read them (Austen etc) rather than because I want to re-read them myself. (I would nearly put Walter Pater's 'Marius the Epicurean' up there with my buddy Marcel, but his moralistic soapboxing and lack of interest in character make the book a bit uneven. But not 'meh', which is the main thing.)
A different one because it's not really a work of literature as such, but 'Chambers' adult guide to numeracy', which someone recommended to me well after my formal education was over. What, you mean it's possible to explain basic arithmetic in simple plain English that anybody can follow, so that the world doesn't have to be split into those who effortlessly 'get' long division and those who will be forever scratching their heads in bewilderment? No, that would totally destroy the fun (not) of school style maths. Better let the subject keep its dusty mystique, obviously.
'Fernando de Lucia: son of Naples' by Michael Henstock is not just the best musical biography I've ever read, it's by far the best biography, and the only book which genuinely brings to life the operatic world of the fin de siecle. It inspired me to write. (I haven't done - yet. But I've been inspired! 
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