studybuddy:
Good to connect with you again!
It's no doubt a tough situation, but bb has laid out some good strategies.
I think you need to have a confidential, personal discussion about your intentions. You can explain to her why you want this degree, how it will help you improve, and perhaps why it would be beneficial to them in the long run (maybe as a future contact, business partner, etc.) Obviously for the last point you'd want to tread lightly as it might seem like an oversell.
As I mentioned in my other post, you may need to be more involved in this process unlike candidates coming from more traditional MBA feeder industries. If she is comfortable with the arrangement, you can provide a detailed outline in advance, work on multiple drafts with her, and just in general be a go-to resource. That's just the price of admission of coming from a non-traditional industry!
If your gut tells you she won't be supportive or won't do a good job (for whatever reason) then you need to look for alternative recommenders. Yes, the adComs want a current supervisor but they are also understanding if you need to select others given conflicts of interest.
Again, please reach out if you need our help!