I don't want to let my girlfriend pay for dinner
Do you think your girlfriend wants you to pay for dinner
I think so.
It is good to want to take care of others. You should just bring enough money to cover both of your expenses.
I am embracing gender roles. I'm a man, men should be the ones who pay for dinner.
That's an outdated way of thinking. It came at time when women weren't allowed in the workplace but now that they are they can pay for the meals too. It's also wrong to limit yourself to gender roles anyway.