I'm so sorry. Really, there's nothing that can prepare you for the illness and eventual loss of a beloved parent. Just know that it will get worse but then it will get better. Remember that your father would want you to take care of yourself in this time of crisis. The knowledge of his care for you is the part of him that will always be with you and it is what you will pass on to your children.
"Tell me, what is it you plan to do with your one wild and precious life?" - Mary Oliver