I got married early in 2009. My wife worked and filed her own taxes while she was single up to 2008. She did not work 2009. I think she has tax liabilities but she does not let me know.
How do I make certain I get my due share of my refund and not apply it to her liabilities. Do I file Innocent spouse or injured spouse form. We do not live in a community state.

You file the Injured Spouse Allocation, Form 8379.

Just file a separate tax return and your tax liability will be separate from hers.

Either file separate return, or with joint return file Form 8379 (Injured Spouse).

You need to make sure you meet the criteria to file Form 8379 first.