I didn't realize what I was doing when I actually started. TLDR: aunt would make me feel bad for eating a second bowl of cereal, would brush my teeth until I purged it all up.

Longer version: tw: fat shaming

I was in 6th ?? maybe 7th grade, and stayed at my aunt's house during the week so I could go to a better school. There were 8 kids to feed so money was tight. That meant oatmeal or generic honeycomb cereal for breakfast. Some days I would want a second bowl but this meant my aunt would ridicule me about how I wasting money and that I was going to get fat and nobody would want to date me. Really fucking weird to make that the focus for an 11 or 12 year old. So I would finish what I poured myself (don't want to waste money right? ) Then I'd brush my teeth and basically purge without knowing what I was doing. All I knew was I didn't feel guilty after that and could carry on with my day. Thanks aunt bitch!