As a fatherless daughter, your confusion is quite understandable. At this time, give yourself permission to feel all your feelings without bottling them up or judging them. You may be experiencing a mixture of sadness, anger, and resentment. You may be grieving the loving father-daughter bond that you never had. The possibility that your dad may die represents the end of hope for the little girl inside of you who always longed for an involved daddy.
You may also be feeling stressed out about the role that you should play as your father gets treatment and then recovers. You may be struggling with whether or not you should be a donor. Several fatherless daughters have written to me recently regarding their aging dads who now require lots of care. They're battling between “honoring thy father” as it states in the 10 Commandments and honoring their instinct to stay away from someone who's caused them so much heartache.
Honoring thy father doesn't require a fatherless daughter to neglect her own needs and the needs of her husband and children. She must put her family first by safeguarding her own emotional well-being, time, and resources.
Honoring thy father doesn't require you to take him into your home and care for him while he recovers. It does mean, though, that you should make sure that he has someone (paid or otherwise) to do this. Honoring their father involves doing kind, thoughtful things such as sending cards and phoning.
It's said that the person who has caused us the most emotional pain is our greatest teacher. You have it within you to rise above the hurt your dad caused you to show him mercy. You have it within you to forgive him and, thus, be a role model to your kids.
If you have a deep faith, this is the time to get comfort and guidance from it. You may want to talk with a clergy person. I know that this is a trying time so please take good care of yourself.