Who is Jet Owens from Practical Magic and what is their importance?

Jet Owens is one of Sally and Gillian's aunts who takes them in after their parents die. Jet had been extremely beautiful when she was younger, although she had never seemed to realize that she was beautiful. When she was sixteen, two different men had killed themselves because of their love for her. Jet had only loved one man and still thinks of him wishing she could kiss him again.