I'm going to give my group member a bad eval even though she spent as long on the project as everyone else
Why are you planning to give her a bad evaluation?
I'm the leader of the group and I want to be reasonable to everyone in giving an evaluation.
That's great you want to be reasonable in your evaluations, so why are you going to treat her poorly? You are not being fair at all.
I just need her to hate herself, so that she'll quit school.
If she did a good job then she deserves to get a fair evaluation. Wanting her to hate herself and quit is not reasonable, and is hypocritical.