What are some significant Catholic philosophical explanations on pain and suffering in this life?

So obviously this is a very important subject, one that leads many to break from the faith. I read a book by Bishop Robert Barron and he didn't have much to say on it, which surprised me. Then I found this http://www.amazon.com/gp/product/0199659303?psc=1&redirect=true&ref_=ox_sc_sfl_title_13&smid=ATVPDKIKX0DER and I'm very interested in reading it. What are some substantial explanations of pain and suffering?