I am sorry to hear about what happened to you as a child and as a young adult. We are taught as Muslims and as women to "overcome" adversity, to submit to our lives, to forgive and to trust in Allah. However, overcoming adversity does not always mean that it will vanish or cease being part of our memories.
You will always have these events in your memory and your healing will take place by accepting that and by resolving the feelings you have with these events.
You have made two important steps already - one is that you remember. Many victims do not remember their abuse, and by shutting it out they create even deeper emotional issues in their lives. Secondly, you are asking for help. I hope you can find a counselor who lives nearby and can be a guide for you during this time of reconciliation with your past.
The first step to healing as a victim is to realize that you were a victim at one time, but to make the decision not to continue being one. As a victim of abuse you were not completely aware of what your options were. Children do not have the ability to perceive and deal with complex external issues until they are at least 12. Before that age children are still developing their sense of self and how that relates to the rest of the world. If the abuse happened (as you indicated) as young as age 6, this could have also effected your development and caused you to go through your 12-year-old awareness later in life. This could be why you feel so strongly about the later abuse that happened when you were 16, but don't feel the same about the earlier abuse. Because, during the time of the earlier abuse, your mind was not able to completely comprehend it.
For this reason, you can also not hold yourself responsible in any way for abuse that happened to others at this time. As a child you did not have the mental or emotional capacity to overcome the situation you were in. It would have been near impossible for you to overcome your own situation enough to "save" others unless you had been lucky enough to have an adult to help you. However, it sounds as if you did not have anyone to help you.
The rape you experienced later in life happened when you were more mentally and physically aware. Because of this awareness you may have felt that you were safe, that you would not have to endure the abuses of your childhood, or that you had more control than you did.
However, rape is much more than a physical act, it is an act of taking over someone on an emotional, mental and physical level. Later, after the act happens, the person tends to see the rape as a physical assault, forgetting that their mind was also assaulted. This can also lead to victims of rape thinking they could have somehow prevented the assault or they were perhaps somehow part of the problem.
You can start to heal by realizing that you were a victim in the past and that you can choose not to be in the future. You can take back your power.
More important than forgiving the people who hurt you, is forgiving yourself for being hurt. Ironically, people who are abused often have an easier time forgiving others but often remain angry at themselves for what happened. Imagine that you are speaking to yourself as a friend. What would you tell this friend? Be as compassionate with yourself as you would be with a friend.
Insha-Allah you can find someone to talk to on a regular basis and can start to heal from these horrible experiences. Perhaps someday you will even be able to help others who have been through similar experiences.
For further guidance, please try the following link(s):
Nowhere to Run...
Societal Causes of Sexualization of Young Girls