I admire the courage it takes to talk about this and am glad you are taking action about what to do to prevent this from happening in the future. I can only comment on the psychological components of this as it sounds like there may be a legal consequences as well. Most importantly — you need to do and say something. Not speaking up about this, and not to stopping what you do not want to have happen sends the wrong message to everyone and is unhealthy for you. Keeping a secret like this can have devastating effects for your well-being down the road.
Begin with your father. Tell him that you do not want to have this man come to the house. Explain that he has done something to hurt you and you no longer feel safe around him. Explain that if he comes you will not stay in the same house with him (and then make plans to stay with a friend if he does so this will not be an idle threat.) It is your decision about how much you tell your father—because only you know how this will be received. However, at 23 you have a right to feel safe in your own home and telling your father this man’s presence makes you feel unsafe is a truth your father will have to accept — or you will go stay with a friend.
What is needed next is a very clear communication to this man that what happened was unwanted and is now cause for ending the friendship. This isn’t a conversation or dialogue. This is a communication to make sure he understands that what happened wasn’t okay and you will not be seeing him anymore.
Finally, let your mom know and explain that you have severed ties with him and are no longer willing to see him. You mother will have to decide what to do, but make it clear you won’t be visiting her if he is around.
These are difficult conversations — but they are necessary for you to continue taking care of yourself. After dealing with this you may want to have some individual therapy to talk about the betrayal by this man.
Wishing you patience and peace,
Proof Positive Blog @ PsychCentral