If I have to tell you my own experience, I must confess that turning an obligation into pleasure, as regards reading books, depends on the reader. Ten years ago, I used to read whatever I wanted... Although it was not usual, if I got bored, I left the book aside a changed it for any other.
I passed most of the time complaining and missing those times in which I sat in the playground to read for pleasure and decided that I had to recover the feeling of getting immersed in the story. That story which I did not want to finish, that character who I considered my friend or an enemy... Those places which I could see and where I could smell the same as the character could.
I turned that pile of books into an opportunity... Even when I could not choose them or give up reading whenever I decided, I changed my mind towards them. Considering that I had to read during the whole year, I bought a new armchair and a nice lamp to accompany the decision. These are special for literature... not to study!! Because I don't need to take off my shoes when I study!!!