It's possible to get derivative status under a U but I'm not totally familiar with the process. I'd call a local attorney or even immigrant assistance foundation who helps with U visas for assistance.
My answering this question does not form an attorney-client relationship. Always retain a qualified attorney before taking any action.
Short answer is no, you will not qualify as a derivative or U-3 status as you were not married to the principal at the time the petition was approved.
However, you should consult with an experience immigration attorney to obtain an actual legal opinion on your question, which you will not receive from a website.
Stanley Dale Radtke, Esq. 415-480-4529. The statement above is general in nature, as not all the facts are known. You should retain an attorney to review all the facts specific to your case in order to receive advise specific to your case. The statement above does not create an attorney/client relationship
I will agree with my colleagues for a no answer. I will also recommend looking into other options by contacting an immigration lawyer.
Shah Peerally, Attorney at Law President of Shah Peerally Law Group PC Newark CA Important: The above is provided for educational purposes only. You should not act or refrain to act solely based on the information provided. Cases differ and success in one case might not constitute guaranty of success in your case. We recommed to talk to a licensed attorney before you proceed. For more information on call us on 510 742 5887