Who knows if they were having troubles, but there were tweets about seeing Alex and Kate eating dinner the same day as the Puss premiere. She was in Stockholm with him, even if she didn't go to the cinema. Also, Gustaf didn't take his girlfriend, either, so it may have been a cast decision to keep things low key. Or maybe Alex and Gustaf wanted a bit of brother time. Alex didn't stay long at the after party because he'd been up early that same day filming wherever they were based and he had to film early the next day, according some account I read. There was also a tweet later about a girl seeing Alex buy Kate a Hammarby scarf, so they were still going places together at that point. I think the lack of Kate at the Emmy afterparties is more suspicious, because she's gone to all his LA after parties for everything since the Scream awards.