How to sell my home co owened

[Bert Kemp]

I bought a home with another person we each own 50% but she took off 5 years ago and hasn't contributed any money towards taxes of up keep and maintenance in 5 years. Now I want to sell the home but am told I need her signature. As far as I know she doesn't care about getting anything from the sale as I basically gave her more then enough money years ago to cover her half of what she originally paid .So what does she  need to do so I can sell this place. I'm in AZ