Good job being assertive and standing your ground. Also, good job on not doing so much for her anymore.
Now, you need to focus on the sitch with the dog and realize that everyone's emotions will be intense, so no R talk for the next few days. Time to be supportive and sensitive to the emotions of all three females in your house. With W, just don't take it too far so that you are being taken advantage of again. You showed your firm, asserive side, and now she needs to see your sensitive, supportive side.
I agree with Sandi that there were some positive signs starting as well. Don't put too much stock into statements like "let me go". My H said stuff like that all the time, when, in fact, he was very confused and uncertain of what he wanted. Don't give up on your M yet.
