To answer your question, I think the difference between sexual fantasy you have and CSA is just that. In your fantasies do you feel like one of the two of you is in control? CSA is about control, not true sexual gratifacation. Sometimes we fantasize about being abused, or humiliated sexually. Sometimes we fantasize about doing it to others. Strangely enough, many of us are addicted to abuse. We don't enjoy it, but we keep going back to those thoughts and fantasies because they are all we know. Thats where difference comes in. Sex should be relaxing, fun, and comfortable.
Truth is the very reason we strive to live. It surrounds and resides within us. Accepting the truths we already know and seeking out those we do not is a direct path to inner balance and joy. For life is not a means to an end, but a journey. Life comes and goes but the truth will always live on.