On a joint return, you can protect your portion of any refund by filing Form 8379, Injured Spouse Allocation. Here's how: https://ttlc.intuit.com/questions/1910698-how-do-i-file-form-8379-injured-spouse-allocation
If your wife died in 2016, you can still file a joint 2016 return.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
