I can’t escape this feeling of being a monster and it eats me alive

I (20M) have recently been undergoing some pretty serious changes in my life. I’ve got a new girlfriend, am soon moving and have a stable job. Most of my life I have been a very isolated person, spending time with my friends from time to time but hardly talking when out (it’s just something I do).

I’ve recently had lots of trauma resurface from my childhood since being shown consistent love and affection for the first time in a long time. This is mainly to do with how I was raised, but there’s a specific memory between me and my sister (who I am 5 years older than) that eats my soul to this moment.

I must have been about 9-10, so she would’ve been about 4-5. We were in my parent’s bedroom, and I was curious about what the vagina was. I remember asking to touch it and tried to spread it apart to see what it looked like, but hardly got far at all before she asked me stop which I did. I remember she did not have any distressing expressions, instead she seemed content. Then, my mother came with her to the door and asked “did you do this?”, pointing to her vagina in a distressed manner. I quickly said “no” and never mentioned it again.

This story makes me feel like I’m an absolute monster. I can’t help but think about how bad what I’ve done is. My mother used to shout and scream at me for everything, so I had to say no because I believed that whatever I did would instigate a massive reaction. I feel awful and am so scared that my sister will remember it as traumatic.

It feels like I’ve abused her, or crossed a boundary because I’m older than her. And I HATE that. The thought of me being an abuser makes me sick to my stomach, I can’t bring to tell anyone exactly what happened. I’ve told my girlfriend about it as well as my mother but not about the details of what exactly happened.

There were other instances of “playing doctor” that occurred, but they were either with other siblings or cousins. They are less traumatic and I don’t feel as horribly towards them as I know it was normal parts of childhood development, but this specific instance makes my heart break.

When I remember it, I want to isolate or just go to sleep. I don’t want to see anyone, SPECIFICALLY my mother and my girlfriend. I just have no energy at all to do anything, I just self-loathe. The hardest part is I can’t determine whether what I did was just curiosity or if I was being abusive. I would NEVER be abusive in any way to anyone, especially my siblings. I wish I never had done it, I feel so disgusting and dirty as a result.

The way I feel about it is this: I would show compassion to anyone who went through what I did on either side. I know that I was a child and I didn’t understand what I was doing, but I can’t get over it. I feel like if I tell anyone I’m going to be criticised and called evil. Even then, after being told the opposite and being shown love and compassion, I cannot help but think what I did was awful. I don’t even know if my sister remembers, and I don’t want to ask in case I freak her out. I always look for signs to see if she is okay, we hardly talk but that is the family dynamic between everyone.