I have developed from a monogamist into a polygamist, my introversion applies only to fiction, and I have noticed the approach of neuroticism that is not inherent in my nature as a book reader.
I obsess only over books I like, which shows in the amount of pages I can read at once without pushing myself. I have also trouble with book-polygamy, which is probably where the neuroticism came from. A little while ago I managed to shorten the list of books being currently read by one book, which means I have now 2-4 books that I currently read. I ignore two of the four because the one I have to begin again, as I haven't proceeded too far, and the other is a feel-good-book that I read when I'm feeling low. Of the other two, one is fiction, and I am halfway through, the second is rather technical.