Definitely don't respond today.... in fact, don't respond tomorrow either. If she calls or bothers you reply CHEERFULLY, "Oh gosh, I've been meaning to get back to you, but I've just been so busy...." and then go on to talk to her in a cheerful way. Do not agree to anything until you speak with your lawyer or a lawyer. And BE POSITIVE. I know that's easier said than done. But you need to be a actor!!! Do not let her know you are falling apart. Do that alone.
And if you feel like you are going to break down or lose it while talking with her then make some excuse that you have to go. You have a friend over and can't talk on the phone. I don't say it's a guy friend or give out any names. Your life should not be an open book to her.
Today/tonight, do something very special for yourself. Stay busy!!! Maybe if you have some unattached buddies to go out with, or even just taking yourself out and then going to a bookstore or sports bar or anywhere else you would want to go....
There is no arriving, ever. It is all a continual becoming.