Why Be Happy When You Can Be Normal by Jeannette Winterson. A mature woman's confessional and partner piece to 'Oranges'. This was an unexpected joy of an impulse buy. I want her to be my friend. We'd fall out soon enough. But it would be worth it.
Except for the impulse buy I could have written all this! Oranges very nearly made my cut.
I stand by my six five but with the new rule (kuh!) about reasons being what they bring to us...
LotR because it is pure, fantastic escapism as it has never been done before or since. So if you want a break from life on the way through, here it is.
The Road and Never Let Me Go because they are beautifully written warnings of inhumanity and what the human race could do to itself. Mad scientists who are tinkering with lumps of DNA and trying to breed X-men should read these as cautionary tales.
Room because I have never read a book that so movingly portrays parenthood as this. The mother is an Everymum figure. If I wanted to give a book to someone to explain how having children makes you feel, this would be it.
Jane Eyre was nearly Pride and Prejudice. But I think on balance, Jane is a better picture of what England was once like. Plus she is more powerful than wonderful Lizzie.
And last but most essential, Wodehouse should need no explanation 
There we go Hully, six books but five reasons