Mother of Mine

Mother/Wife of Mine was part of a criminal family called the Family of Blood. She resembled a gaseous entity prior to possessing a maid named Jenny.

When she was caught by the Doctor, after she and her family tried to take his life essence, she was thrown into a event horizon of a collapsing galaxy, to be imprisoned there forever. (DW: Human Nature/The Family of Blood)

Trivia

The final fate of the Mother being thrown into a black hole did not make much sense, as a black hole based on real world theory would have killed her once the tidal gravitational pull took effect, objects pulled into a black hole are shredded into subatomic particles and emitted as"hawking radiation" however Black Holes in the Who universe may have a different science to those of real world black hole theory, she may have ended up in a universe similiar to Omega.