When I think about it, that my dad was sexually abusing, penetration and everything you can think of while going back home and having sex with my mom. It's almost like I was having sex with her in a way. His penis would go inside my mom and also inside me. It's like almost having a sexual experience with my own mom, that's how close it was. Now I think about it more. What does it mean if she continued to have sex with him even after she found out about the abuse? Does this mean my abuse turns her on? What if she already knew what was going on when it was happening and she didn't do anything because it was normal to her? It's a realistic possibility. When I think about it, would I rather my abuser be a male or female? It would make me feel better if it was a female since I was a guy. I sometimes imagine her doing it.

Some of the points you bring up ignore a certain reality.

It wouldn't matter about the sex of the abuser, the abuse would be equally devastating. Some of the avenues we explore during our healing path are counterproductive...it is the way it is. Shattered boys can't find their way without a few steps down non-productive paths, all spiritual journeys are punctuated with steps both froward and backward.
Your Mother was responsible for protecting you and she failed to be able to do that. She didn't stop him from abusing you, she may have been unable to stop him from having sex with her as well.
You were abused by both your parents...sexually by your father, and failure to protect you by your mom. Many times you may find yourself wondering about the different relationships involved...I myself as a victim of incest was obsessed for long periods of time about the different involvements of the family members with me. The reality is that I needed to reclaim parts of my own identity and make my peace with the fact that whatever happened, whatever I felt about it, however it made me feel and crippled my future, that I was sick of toting it with me. I had carried it until it was like a cross, threatening to drag me down with it. I still remember vividly deciding to let it go and how the burning ritual made me much more free. I urge you to seek help in discussing the history of your own incest / abuse at the hands of your father. Your own survival is amazing...and not in a small way but in an EVEREST highest peak way. Conquering incest and deciding to live through it is beyond difficult or challenging...it is life threatening and one of the pivotal decisions in our lives. sorry if I have offended in any way...just couldn't let it go bro...love ya...Geoff