I'd say it's definitely a phase. Nina was like this a few months ago, it was all about daddy. Now though, it's all about mummy. He's at home with you a lot more than what daddy, or other people are. I know it hurts when the reject you for a cuddle, but try to not to worry about it. Give it time, and he'll come running back to you, and you'll be desperate for a little space from him!