Seller wants out of contract

[Phil Dodd]

Found a off market deal last Monday and executed that night.  I gave seller cash deal, no option and 40 day lease back.  Seller  was trying to buy another house and needed her house under contract so she could remove contingency.  Well that deal turned into multiple offers and she did not get her contract accepted. Now she doesn't want to sell her house to me. We are suppose to close this week. I'm sure others have had this same thing happen. How did you chose to resolve it?