This post combined with your new post about not being allowed internet access in your bedroom hints at a different story than a narcissistic parent. The fact that you aren’t willing to use the computer in the public spaces in the house and want to sneak access back into your bedroom says your parents fear inappropriate use of the computer, whatever that may be. And if she comes in and is hanging out in your room, it’s not to annoy you, its because she’s scanning everything in the room for signs of stuff they think you shouldn’t be doing or shouldn’t have.

This isn’t to say you did something to provoke suspicion, some parents are really conservative and just suspect kids are up to trouble. But trying to get a better way to lock the door combined with trying to sneak internet into your room gives off alarm bells to parents.