This is assuming the woman is okay with this arrangement.

Edit1: Assuming you want kids too

Edit2: I would pay for everything, she has a great job, and we would live in the same house hold.

Edit3: Thanks all. To add, a private PM suggested I get married and look into a pre-nup/at-will arrangement that provides $X to her within a set time frame before or after in the event of a divorce. Thoughts?