When I'm having dinner with my girlfriend and I ask her to eat more, what should I do if she says she's getting fat?

She is worried about whether you will still love her or hate her if she gets fat.

As long as you tell her that she has gained weight and you love her just as much or more, she will feel at ease and can eat with confidence. What she wants to hear is your guarantee.

Of course, if she really gets fat, whether you still love her or hate her when she gets fat is your problem at that time. It has never happened, so who knows.