Sexual Abuse Support Group
Sexual abuse is a relative cultural term used to describe sexual relations and behavior between two or more parties which are considered criminally and/or morally offensive. Different types of sexual abuse involve: Non-consensual, forced physical sexual behavior such as rape, incest or sexual assault, or psychological forms of abuse, such as verbal sexual behavior or...

I also felt my mother was too sensitive to tell but my therapist kept saying "She is an adult and can handle the truth". It is very common for those of us who have survived abuse to want to protect others from the horrors we endured. But, as my therapist says, your mother is an adult and she can handle the truth of what happened to you. It is not your job to protect her - it was her job to protect you. Please do consider telling your mother because it is very unfair for you to have to see this guy at all. You deserve support and you deserve to heal. I am not sure if you are still seeing a counselor but if you are not I would urge you to do so. It is possible to heal from what happened and you do deserve to heal.
Being a person who has been abused a lot, I sympathise whole heartedly.
Big but, are humans really humane... I fear not...
What is humane?
From what I understand of life is that people whom that have suffered no abuse are shockingly disconnected from the world we perceive.