I agree!
The writing for Nick and Carla the last few weeks wasn't great. Nick fought so hard for Carla over the year as a friend and lover. I just don't think he would have been that cruel. Maybe in the heat of the moment but in time he would have at least spoke to her. I suppose that's his head injury aswell. Also Carla made no attempt to fight for their relationship. She just leaves. Nick doesn't even know the full story and has now disappeared from screen. They could have at least had a heart to heart agreeing that Nick couldn't move and she couldn't stay and her leaving on better terms.