1st preference category. unmarried (never married?) son/daughter of US citizen?

[xanadu]

what does unmarried son/daughter of u.s. citizen mean? is it the same as never been married?

[xanadu]

what does unmarried son/daughter of u.s. citizen mean? is it the same as never been married?

[Mo]

Unmarried at the time of the petition. Previous marriage is not an issue, if there is one.

[xanadu]

I was single when my dad (a us cit) filed petition for me, which eventually accepted under the 1st preference catetory. while Im still waiting for the visa availability I got married. Am I still classified under the 1st preference category, or would it be adjusted to the 3rd preference category. If I divorce my wife, under what category should I fall in?