My partner hates the choices my RPG character makes. Do we need separate campaigns?

I let my rogue keep the reward instead of returning it to the villagers. My partner put down her controller and said, "That's such a horrible thing to choose."

We started this role-playing campaign together. I wanted to see what happened if I played a selfish character; she wanted to help people and get attached to the companions. At first the contrast was funny. Now every major conversation turns into an argument before we choose a response.

She says she isn't judging me as a person, but the decisions make the shared story unpleasant for her. I said it was just a game, which ignored the fact that the story is what she came to enjoy. I don't want to spend the campaign defending my actual character because my fictional one steals rewards.

Can we agree on a shared tone while leaving space for different roles, or would two separate campaigns be kinder? We've put ten hours into this one, and neither of us wants to keep those hours by spoiling the next ten.