we were just kids

when I was 13, I got my first boyfriend. he was my first kiss. I have since found that I am a lesbian and it was extremely hard to break out of the heteronormative cycle I was in. my mom loved my first boyfriend, we had been in the same grade school class since we were 5 years old and she said that one day we would get married. I knew he had a crush on me the entire time and eventually, I grew curious. he kept asking me to kiss him and I was hesitant, but it got to the point where I just did it to make him stop. I guess he grew comfortable enough around me that he felt he could get away with anything around me. he would smack my bum a lot, which I thought was just playful so I did it back to him. he wanted more from me and groped my chest without asking. I felt so dirty when he did it. it felt like I had to grow up right in that moment. I pulled his hand away but I didn't stop kissing him, I felt like that was what he wanted so I gave it to him. I got so in my head about it that I distanced myself from him and severed our relationship. I tried to tell my mom but she dismissed my being upset with him being 'handsy'. she was so proud of our relationship that I think I was only doing it to make her happy. I still don’t understand what happened, and I'm 21 now. if a full-grown man did that to me it would be mortifying to others. but we were both kids and I haven't stopped thinking about it for years. is that sexual assault? I feel like it's my fault that I led him on like that. and that this isn't as big of a deal as I'm making it out to be. why do I feel this way? we were 13 and I still feel violated and ignored, it's been 7 years. why is this so hard to get over? I'm graduating college soon with a degree in criminal justice, I want to be a victim's advocate. maybe some other 13-year-old girl can tell her mom and she will know where to go to understand what happened to her. I want to be the person to help but I still don’t understand what happened to me. why am I like this?