I'll lend my paperbacks once I have read them. I admit to being a spine bender, but I never bend back the front covers of the book (I use a hair "jaw clip" to hold them open when I'm reading them if I only have one hand available, i.e. I'm eating or cooking). I also no longer dog-ear pages like I used to do in high school and college.
I do have a few books that I will lend to no one. They are the leather-bound, gilt-edged volumes of
The Complete Works of William Shakespeare and
The Iliad and The Odyssey. No one gets to borrow those books. I also have only lent my hardback editions of books to one person and that was because I knew he'd treat them well. He has always returned them in the condition in which I lent them. I will admit to testing him with paperbacks first, though.
I read everywhere, all the time. My hubby makes fun of me because I have a handtowel right next to the bathtub that I use whenever I need to turn the page while taking a bath. This way the book doesn't get wet. When I get out of the tub, I have another towel that I drape over the book, just in case I drip while towel-drying my hair (water goes everywhere, I swear!). I learned these lessons the hard way.
I will admit to having left a book I was reading outside on the deck and it rained. I was devastated. I had only read the first two chapters. When the hubby saw how upset I was, he asked, "Why are you so upset, hon? It's only a book."
I'm not sure he understood my cry of "Sacrilege!", since he's not a reader. I equated it to me saying "It's only a football" if his Roger Staubach-autographed-ball got eaten by the dog. I think he got it.