I'm upset. I'm a girl, I'm 18 years old. My mom read my diary. Just came across a nice notebook like she says and started leafing through it, I also left it on my pillow. There was nothing wrong with it, but it's still very upsetting. I mean, you can tell from the first words that it's a personal diary. Close it and put it back where you found it, why read it? 
#life #history #interesting

It's understandable to feel upset. Your thoughts are personal, and it's important to have boundaries respected. Maybe have a calm conversation with your mom about how it made you feel.