Those parts of the interviews made me cringe too. It's an interesting film and I admire him for continuing to promote it in the middle of this crap in his personal life.
However, fans (particularly the young ones, who have only known our sleb-obsessed culture) don't understand that this person who is paid millions to be looked at, isn't always their property to look at. And the paps/journo enable them, are their conduit. It's the reality of fame in the twenty first century and if the actor can't handle it then they should work in theatre instead.
Plus, their relationship did help flog movies. They might not have planned it that way (I don't think they did, though many disagree) but Edward & Bella got confused with Kris and Rob for some fans.