Yeah, all the way through, I kept waiting to see how either the Viper had twisted things around and show how she had convinced him that this was the right course of action, or show something that had fundamentally changed who he was. The fact that it happened somewhere off camera definitely left a very empty hole in the movie for me.
All that being said however, it's easily my favorite of any of the movies that have included Wolverine.
It was still a fun Wolvie movie. I just didn't like that the one decent guy in the family was made into the bad guy.