You really can't control if your W is upset or not. So send what you feel is appropriate and keep moving forward. Honestly, you are your own enemy here as a simple e-mail should occupy two days for you!
While I am not a C I do have to disagree with the pursuit your C is suggesting. Her strong reaction to the flowers should be your gauge.
Honestly, if you are upset she has not repaid the joint funds she took or has failed to help with the house you BOTH own and are trying to sell then only you can change that.
I see no problem requesting a meeting with her to establish tasks you BOTH will need to work on for selling the house and to see about how you will be reimbursed for the funds she took.
I know you know you can't force your W to have a R talk but you certainly can protect yourself and request her help with the house as she will benefit from the sale as well.
