Your post reads like a fantasy right until the point she freaks out. I do wonder how many other couples have intentionally or unintentionally induced lactation during covid lockdown. If a woman is trying to induce lactation, her instructions are extensive stimulation in several sessions per day, which would not normally be practical.

Has she ever been pregnant that you know of (even if not carried to term)? Inducing lactation in a woman who has never been pregnant is supposedly difficult. Some of her sensitivity about the issue might be explained if she is concealing a past pregnancy from you.

As you've certainly found out from your research, milk supply is based on demand. If you or she express, pump, or otherwise "get out" the milk, that encourages more supply. If she wants it to stop completely, that means slowly reducing how much is expressed in spite of the engorgement, potentially wearing a sports bra 24/7, and perhaps using cabbage leaves for discomfort relief and to dry up supply. That can take several weeks.

I hope she comes around to this being normal and something you can share. She wanted and asked for extra attention to her breasts, so it would seem she could be amenable to the whole experience which could mean endless daily breast orgasms for her. If you were able to establish a steady routine for getting out the milk, the oversupply and discomfort issues should resolve by equalizing her supply to (your) demand.