Scott, I can really appreciate your anxiety right now.
You have many more options than what seems to be before you, and honestly you have more than what my brain can come up with. Perhaps the bottom line is whether you write this note or not, but there are many options as to how you do it or not do it.
She definitely is playing boss, telling you to jump and expecting you to say how high. And it appears she is very badly behaved when she does it.
I personally would like to see you tell her you are going to have to look over what she brought to you. When she goes off, tell her you'll talk to her later when she's calm, etc. She can wait for her money.
That said........she will react. She will likely step up her game. To me, this is like a child throwing a tantrum. They keep it up when they get results. If you eventually give in while they are throwing the tantrum.....they get trained for endurance on the tantrum.
I know you are fearful about going dark. It centers you, it calms you it makes you more mysterious. You probably are dark enough, but you need to not be available to her every whims...not that you are....
REAL GIVING is important. It's important to respond to your partners' needs. But this is different.
There is no one right answer, Scott. Don't second guess yourself or your advice.
If you choose to sign, you will remove her resistance...it could be a good way to go. You will still be connected through your kids....I'd bet on you two remarrying.
If you choose NOT to sign, you can buy time, stall and train her.
What are you up for?
(And of course, there are more options than these...you just have to think of them or have someone else think of them.)
sg Love is PATIENT, love is KIND, LOVE never fails / DB since 2001