I think he was meant to be with Giselle because she showed him more to life than Nancy who was so bitchy and way too possessive with Robert as she wanted the fairy tale life whereas Robert wasn’t ready just yet as he said the lovey doupy version you talk about is fantasy and one day you wake up and your in the real world. I think he was afraid to fall in love because he probably had a wife and she left him for another man and he won custody of Morgan and he got the apartment for the two of them to live in. Also he showed his affections to Giselle at the ball when he sang to her and danced with her to the song So Close at the ball because Giselle said to him earlier in the film that you should sing to the person a beautiful ballad and it will show your affections to that special someone.

Without no question

That was in the movie