In the year you divorced and she took full ownership of the home you were supposed to report that on the form 5405 ... if this didn't happen 2016 you will need to amend your prior year return to reflect the change and mail in the current year return.
In the 5405 section you should come to this screen ... this will release your obligation to pay the credit back.
To report a Homebuyer
Credit Repayment -
·
Click on Federal Taxes
(Personal using Home and Business)
·
Click on Deductions
and Credtis
·
Click on I'll choose
what I work on
·
Under Your Home
·
On Homebuyer Credit
Repayment, click the start or update button
Also see this TurboTax
support FAQ on the repayment - https://ttlc.intuit.com/questions/1900658-repaying-the-2008-federal-homebuyer-credit