Invasion of Privacy

Sylvannas
What do you consider an invasion of privacy? I seriously want to know. I feel like I have no privacy and it's driving me insane. I'm in my 20s and ordered some high heels for a pole fitness class. My mother, who I live with right now, proceeded to open my mail (all 3 packages) and sent me texts while I was at work mad about them. Sorry? You shouldn't have opened my mail. It's not like it was something extremely sexual or something. Now she thinks I'm going to become a stripper. She was furious when I bought an in home pole. Same with the shoes. Like really? They are high heels. Hot pink, high heels that are 7 inches, but high heels nonetheless. I just feel like she stepped over a line and I'm not sure how to broach that subject. I don't bring stuff like this up to her because if I say pole fitness she thinks stripper, no. It's exercise and she refuses to see it that way. She's very conservative. Is what she did even acceptable? I don't want to ruin our relationship with a fight but I'm not ok with that at all. She treats me like I'm 14 or something.
***For everyone who thinks the classes and pole were expensive. Groupon had a huge sale on the classes, making it cheaper than a gym membership. The pole was a Black Friday deal and also super cheap. I'm in the process of moving out and will be gone within the next month. Also the pole is not set up. It's under my bed, so I am not flaunting it in her face, I'm respectful lily waiting to set it up until I have my own place.