As you know this is not appropriate which is why you are reaching out. It is very dangerous to entertain even fantasies because this leads to fulfilling this fantasy. There could be several reasons for why you fantasize about her. One may be that you don't have the genetic connection and have become physically aroused by her. This is at times exacerbated by the fact that she trusts you and sees you as a father figure. This is then perverted into this fantasy that has a life of itself. It may be the case that you have a sexual addiction and she is just the focus of this addiction. Either way you need to find a therapist in your area so that you can process this before you act on your perversions. You can find a therapist in any area by checking the site for the American Psychological Association. You can ask a therapist if she has training in sexual addiction. In addition there are 12 step meetings in most states for sexual addiction - Sex Addicts Anonymous. When you ask for help you will be able to share the secrecy of your thoughts without fearing the embarrassment. You can even participate in therapy online by Googling online therapy. This may be taking on a life of its own but it doesn't have to. Be proactive and find out why you have focused on her.
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