HOW DO I TAKE CARE OF HER WHEN SHE'S ON PERIOD?

You can't do anything except listen and be sympathetic. This isn't something that can't be 'fixed,' so don't try. And don't offer 'solutions' because she'll have heard them all. Just be as supportive as you can.

There us nothing you need to do but listen to her. Many girls get pain when they have their period. She most likely knows what works best for her to minimize this pain..there are over the counter medication, sometimes putting heat on the area helps, sometimes exercise and sometimes just laying down . .the only recommendat ion besides that is if she does have it a lot and it is severe she might consider talking to her doctor.

But if it isn't really there is little you can do but be a sounding board, letting her know you care and comfort to her on the phone or FaceTime ..honestly there wouldn't much more you could in person.

He could be a scientific genius and solve the problem that is menstruation. He could make $billions.

There is already a solution.

Birth control pills. They can be taken for months and months at a time with no ill effect, and no period.

Babies?
Unfortunately, if you want one, ya gotta involve menstruation until you fall pregnant.

Menstruation isn't a problem.

Unless you're trying to get pregnant, and especially if you're trying NOT to, every woman LOVES getting their period, we just hate having it.

Which most certainly does not mean take all of the abuse that she might decide to dish out...being on the rag is no excuse for bad behavior.