Split earnings?
Unless you understand for yourself and explain to her that you might not profit for the first 6 months - 1 year of operation, you'll both be in for a rude awakening. If you pay as you go/depend on her to make content as it goes you will fuck over yourself and affiliates but blowing your nut too fast and not having a site with legs.
Shoot a TON of content with her, own it outright (for the day she changes her mind.. and that day WILL come) and hope you make a dime. That's as real as it gets.