Fantasy or Sci-Fi story where the characters fight with shapes and colors. The daughter is given in marriage to stop a war with a neighboring country.

[Tru]

I read the book in the mid 2000's but it could have come out as early as 1990. The girls dad fights with warped shapes which makes him dangerous, but they don't know all of her powers yet. The guy she marries lives with his abusive Grandfather and always wears black. The Grandfather abused the mom and him, I think somebody is named Cloud Dancer but not absolutely sure.

[Rainbowheart]

Was this book for teens or adults?

[Tru]

Adults