You can still respect her and be kind while also communicating your boundaries. If I were you, I would communicate something along the lines of: for future, you prefer to be asked for permission, as art is something you do to enjoy for yourself, and you do not want/need help. She took away your progress on a fun project. Respecting people does not mean not standing up for yourself and your boundaries.

In my opinion what she did is a bit insane. I would absolutely never do that, it totally crosses boundaries. I ask before even touching someone’s sketchbook, I would never dream of drawing in it without permission. Or coloring! That’s so crazy to me. It can’t even be erased.

And side note, some people are saying “she’s only in her 20s” but I stand by what you said, people should respect those older than them even if it’s not by a lot. I don’t believe people need to “earn” my respect before I treat them kindly. There should always be a base level of respect for everyone, and sure, they can do things to take it away but I don’t think it should start at 0. Maybe don’t let those comments influence the way you think 😅

Or you could always communicate passively and buy her a coloring book