For me I remember being brutally molested by my aunt from when I was 6, off and on until I was 11 or 12 (I struggle with my time line). There were other perps I remembered, but a couple I didn't.
When I was asked by my first T if I was molested by my first step father, I said no because I didn't remember anything. However, I would also get an incredible feeling of terror and just saw black in my mind, literally. Like looking at a tv that is turned off. My body would also get even more tense and my flight response would kick in. I wrote it off as just remember being non sexually abused by him, because he was extremely physically abusive to me and I remembered a few of those events.
However, I used to have a recurring night terror. I was a really little guy (I was seeing this first person but felt like a small child. Hard to explain) but I would walk up to a door and that was as far as the night terror would go because I would always wake up in terror, sometimes screaming, but always shaking and sweating and a feeling of wanting to die.
I had this same night terror off and on growing up. When I was in my very early 20's I started to have it on a regular basis. When I started to have it almost every night for a couple of weeks I found my first T who specialized in child abuse because there were other night mares I had of this same step father beating me.
I told her about the dream and we started to work through the abuse a little trying to figure out what was so important about this night mare. We worked on other things surrounding him and the non CSA abuse (I still didn't realize he had sexually abused me at this time) but we would usually go back to the night mare.
After about 3 weeks of this she talked to me about hypnosis and how she thought that she should put me under hypnosis and go into the night mare very cautiously. I was scared to do this but I also knew that it could reveal whatever I was terrified of and of course work through it.
Sure enough, we go up to the door and I went into a terror state. She calmed me down and asked if I could open the door. I did and BAM, I had a rush of fragmented memories and bolted out of the hypnosis state and just wept. Wept like I had never wept before.
I only saw bits and pieces but enough to know that it was a rape event. We tried for about a month to learn more but that was as far as I could go and I had to stop therapy because I lost my job.
The nightmares stopped for a couple of years and then I forgot about it. Frankly I know I wasn't ready yet to deal with it.
Over time I started to remember quite clearly what happened just before the incident. But the actuall event was absolutely black to me, like a turned off tv. But the feeling of absolute terror was there.
I'm going through therapy again, and things have been getting clearer. I still can't remember much of the actual rape yet, but what I do remember is enough for now. I have to process what I know of the actual event in order to get deeper into what happened.
TRIGGER ALERT!!!I do know this, I was gang raped in a Satanic Ritual at 5 yo. This was some kind of Hell's Angel initiation for my Step Father before he got his full patch (It seems initiations are different for each member, depending on what their role is, the individual, etc.). There were two adult males (one was my 1st SF who I thought was my real father) and 3 adult females. I was first analy raped by my SF, although I only remember the first penetration and my memory blacks out from there. There is also evidence that I was drugged but we can't pinpoint exactly what it would have been.
However, the memory picks back up with about an 11 or 12 year old boy bolting in and screaming. "Stop it! Stop it! You sick bastards!!!" Then he screams things that I don't exactly remember in detail and they all leave. He rushes to me and tries to calm me but he is panicking. He's trying to help but he's overwhelmed. He gets towels and starts to clean me up. I was tied up so I couldn't see things very well but he cleaned up my belly, my penis and my butt. I see blood on the towels.
END OF TRIGGER ALERTThere is much more detail of this event before and after but not worth stating here, and more memories pop up from time to time (I'm officially taking a break from working on that directly right now because it was reigniting PTSD).
I do know this. Everyone is different on what they can handle and what they can't. If it is too bad, yes a person will block out the memory and that is a natural defense mechanism for the mind. Your subconscious usually will only allow you to remember as you are ready. There are exceptions, but they are not all that common.
It doesn't mean that the crap we remember is easy. Hell no, we all know that too well. I'll tell you this though, if it came flooding to me at once when I was in my 20's I would have blown off my head to deal with the pain. I tried suicide when I was about 13 but there was some divine intervention. Someone wanted me alive.

I'm starting to understand why as time goes by.
Alex