What is the title of this vampire novel from the 80's?

I read a vampire novel in 1989 or so while drunk. I don’t recall it being a particularly good story or a well-written book, but not as bad as some of the airport novels I’ve read in my life. It’s about a girl who becomes a vampire, written by a female author. I don’t recall her being bitten by anyone, but she gradually becomes a vampire through the telepathic control of someone she never meets. All while working night jobs, avoiding garlic and developing an eating disorder. I believe it takes place or ends up in the west somewhere, Arizona? She hides in the (unfinished?) basement of some family’s house and (I’m not really sure, I was drunk while I read it) kidnaps a child. She becomes invisible and dances under the streetlight while a possee is searching for her.

At the end of the book, she is confined to a mental hospital and doesn’t eat for over a year. Her psychologist tries to coax her out with a pretty little cake, but she refuses it. The cowboy who captured her is coming under her telepathic spell, but she’s not really in control of the whole process.

Sorry it’s not much to go on, but it’ll drive me crazy if I can’t figure out the title of this book.