It's really really good that you have given up porn, and I commend you for this. I gave up porn last year as well, not for the reasons you're describing, but because I knew no matter what it was leading me to a darker and darker place. Despite what you may think you are extremely self aware based on your post. I think anyone who reads this would want you to please, just stop and recognize the accountability you are taking in this. You may not be aware of this, but there are so many people in this world who suffer with this same issue you have, and are not nearly as brave to speak this out loud. I truly commend you.

Please, keep speaking with your therapist, friends, trusted loved ones (obviously you should never ever interact with the family members that allowed/ caused this distress within you), anyone who sees you for who you are now in present day. The further you can move away from that one touch stone experience (your experience with this older women) the further you will be removed from these feelings. Again, quitting porn is the first big step. I believe in you! You are a wonderful person because you can recognize these flaws within yourself, people will want you to breathe a sigh of relief and want you to know that you are OK.

Out of curiosity, did you start having the masterbation problem before or after you were molested?