my fiance had a k1 visa before we met but did not use get married on it, can she apply for another visa?

Answer 1

Yes, she can, as long as she didn't overstay or do anything else that might exclude her while she was in the US not getting married. That's exactly what a K visa is designed for; to try out the US and the possible spouse before diving in, and no hard feelings or immigration complications if it doesn't work out.

In fact, we like second-time K's. Hope springs eternal.