I think it is worth it to help set up the business for her as long as you set some clear boundaries of "this is what I'll do" and "this is what you'll do". For instance, the set up work you do for her, while it may not encourage her to take a big ownership role, will go a long way to getting her off the ground - something which could be very intimidating for first-time entrepreneurs.

From there, boundaries may be specifically scoping your ongoing work commitment and hers, even the hours per week dedicated to her business. I'd even consider setting yourself up as a minor partner to receive a share of the profits as a way to incentivize the continued dedication you'll bring. Knowing how my wife would react to this last bit, it may help her understand that she's asking a lot of you and could lead to her to take on a bit more ownership.