I know the feeling, I have a lot of holes in my memories, the younger I was the more holes. I remember enough to know it was not good and, I'm sure I have good reasons for forgetting what I did. Likely worse than what I do remember, if that's possible.
Given some things I've recently recalled, and people I've met (or should say re-met, knew him in one of those lost periods), I suspect those locked memories are very dark and nasty, to say the least. I'll get to them in time - when I'm in a place to be able to handle it.