Yeah, I agree with serafena. You have really been so supportive of her and she is just in so much denial.
I have bipolar and I'm sorry to say that sometimes it takes falling flat on your face before you realize that you need the help and need to take your medications.
In the meantime you need to focus on what she is doing to you and your family. None of you deserve that. Perhaps with you making a stand with leaving (which I think is totally appropriate) she may start to think...maybe not, but in that case you would know that you are making the best decision for you and your children.