How to recall somethin happened in the past

Hi,

I grew up in a toxic family environment from around the age of 12. Three years ago, I left home to study elsewhere, and being away helped me a lot. During that time, I noticed that I could remember difficult things from my past more clearly.

Right now it's vacation, so I've had to come back home for two months. I usually stay with one of my aunts, but she was away for a week, so I had to stay at my family home.

Yesterday, something upsetting happened while it was just me and my mom at home. The strange thing is that I can't remember exactly what happened. In the past, I used to forget bad memories as a way of coping, and it feels like that's happening again.

Has anyone experienced something similar? Is it possible to block out stressful events so quickly? What can I do about it?