I Stole From My Best Friend

Okay, I have to get this out. I feel like I'm going to explode. When we were kids, like maybe 10 or 11, my best friend Sarah had this awesome rock collection. Her grandpa gave it to her. I was so jealous. I wanted it so bad. One day, I was at her house, and she went to the bathroom. I saw the box, and I just... I took a few. Just the really shiny, cool ones. I told myself I'd give them back, but I never did. We're adults now, and I still have those stupid rocks in a box in my closet. Sarah probably doesn't even remember, but I do. Every time I see them, I feel sick. I don't know why I did it. I was a brat, I guess. I should probably just mail them back to her with an apology, but I'm so embarrassed. It's been like 20 years. What would she even say? God, I'm a terrible person.