Since this is a thread about the new pope, note that Catholic doctrine interprets that passage to mean you can only divorce if the original marriage was invalid. The Greek word, porneia, has more literal or abstract interpretations depending on context. Protestants and Orthodox[1] interpret it to mean illicit sex, particularly adultery, but Catholics interpret it to mean something closer to incest, which would imply a marriage was never valid in the first place. Catholic doctrine argues this interpretation is easier to square with the preceding statements by Jesus in Matthew that "So they are no longer two, but one flesh. Therefore what God has joined together, let no one separate." That is, that marriage is indissoluble by man--i.e. a spouse can't dissolve a marriage just be screwing around. And also squares with Mark, who mentions no exception. OTOH, that's arguably asking too much of the text.
[1] That said, depending on which Orthodox theologian you ask, Orthodoxy doesn't permit remarriage, either. Some Orthodox will tell you that a second marriage isn't a sacramental marriage; that the original marriage is never dissolved. Rather, "remarriage" is a form of "Ekonomia", wherein the community sort of ignores some misbehavior, or withholds judgment, so as to avoid cutting a person off entirely. Pope Francis explicitly mentioned this concept of "ekonomia" when discussing his preference that (civilly) remarried Catholics be permitted the Eucharist. And he arguably had this concept in mind when advocating for the blessing of people in same-sex relationships.