I have been through a lot of this kind of thing and can relate to all that you say. I have suspected things, known them without knowing how I know because the memory is missing, but I know. I also know what others have said, things that wouldn't make sense unless my suspicion was at least 90% right.
Then, eventually, I get a major flashback of a new memory and the thing I've suspected all along is a part of the flashback experience. It's too strong to be "filler". So I get the memory of it, and it matches what others have said or done who were around back then, and it confirms my suspicions about what occurred. It's not the same thing has having normal, continuous memory, so it doesn't feel 100% ever, but 99% just has to be enough to be the 'tipping point' to believing myself because that's all I'm going to get, as good as it gets with PTSD.
For one of mine, I felt very upset by this doubting feeling. So take what I did about it with a grain of salt; I don't know if this would be helpful or make things worse for someone else. I trusted my gut instincts and it payed off for me in this case. I do think that sometimes exposure therapy kinds of things only make it worse. It has to end well, you know? Sometimes you get lucky with it.
I found it very healing for a particular flashback memory to have my husband help me use Google Maps and earth satellite images to (from the safety of my own home and comfy sofa) 'go' to the road/river from my childhood home address, to revisit the image of the road near the scene of my trauma. By myself, I got too dissociated to find it. I got frantic feeling.
My husband helped keep me calm and validated me. We both looked until I was 100% certain I found the exact place on the side of the road where we got out of the car. I know it sounds terrible, but it actually (surprisingly) was a healing feeling to see it looking like a normal place with sunshine (it was raining then) and not dangerous to me anymore. It helped me feel that the memory is correct, and I'm right about it, but it's from a long time ago and cannot hurt me anymore. It helped me to see how the drive I remember fits the actual drive and to have another adult validate how clear my memory of what the drive was like and how it actually is. I was validating and calming, which is what I guess I needed at that time. It calmed me down. I was able to accept it and talk about it, and process some of the anger. I still feel alot of the anger, and I'd like to move further in processing through that to the other feelings I know are there underneath, the feeling of losing a safe mother and having to parent my sibling from that day forward to keep her safe. I lost a lot that night, and had true PTSD the next day, shaking, dissociating and hiding from my mom and worrying about future attacks.
The pain of knowing that my mom meant to harm my sister (and I) there will always be with me as a betrayal of trust, and it does make me feel anger, but not as much as it did after the flashback. I do think that a safe way of doing one's own exposure therapy can be extremely helpful and empowering for this very feeling you are talking about of self-doubt.
I hope you could find a safe way to maybe reframe this after accepting it. Accepting it is a very hard step. After that acceptance, the emotions do sink in, and that is rough. Getting support and understanding and reframing and putting it in perspective is the thing that helps me relieve the suffering. The pain is there, but not the suffering, once it is processed in these ways.
From what you have said, I fully believe what you think is real, is real. From your descriptions, it sounds to me like you know what you're talking about. I personally can relate to a lot of what you said.
I also have found the injuries when going to for medical care and have been asked how I sustained the injury. I am quite embarrased that I cannot answer the dr. because the memories are exactly as you describe. As years go by, I realize that I don't have to remember in the normal way to know that the injury is there, who caused it, and why it was never talked about and to say with certainty that my parent did it on purpose if asked now, even though the memory is a blur, for good reason.
I validate that you have found the injuries and have had to keep secrets from yourself even for a long time. It's okay to let it come out now and I believe you 100%.
