I often hear a version of this concern in memoir classes/workshops that I teach:
I want to write a memoir, but my memory isn’t very good.
To this I say two things:
1. First of all, your memory is probably a lot better than you think. You might not realize how much you actually remember until you sit down to write. Once you unlock one memory, often a flood of memories will follow. Trust the writing process.
2. All right, let’s say your memory isn’t very good. Perhaps there are some key moments in your life that you just don’t remember or don’t remember well. To this I say, That’s OK!! Let your reader know that by saying something like, “I wish I remembered this better, but I just don’t…” Explore WHY you are having a memory problem. If this was a crucial moment in your life, or a significant turning point, and you don’t remember it, WHY is that? Why do you think you have a block in your memory? In terms of story, the reason why you DON’T remember can be just as compelling as actually remembering it as it happened.
Having a wonderful memory is great for writing memoir. But the reverse is true, too. The nice thing about memoir is that anything goes. Once you get past the idea that your memory has to be perfect in order to write memoir, you will be off to the races!