So let her rent another place then! She doesn't need a divorce to rent somewhere else. And you don't have to help her buy another house so she can "get past this".
Don't ask her to put off the D. Don't MENTION the D. If you must, let her know that you'll be contacting a lawyer to see how to get you off the mortgage.
Buy some time and BE PATIENT! Let things sink in a little before reacting...
