My friend said obsidian is a bad crystal. Is it really?

Newbie here asking!

I have been super drawn to black obsidian and after small pieces I even got a huge piece for me because I just couldn’t walk past it.

Later my friend told me that it is a bad stone/crystal and everyone should avoid it. I asked ”Why? It protects, absorbs negative energy, it grounds, etc.” but she said ”everyone thinks it’s a good stone/crystal and protecting because it’s black but it just calls for everything bad and negative into your life.”

I tried to google and so on but I cannot find anywhere that it would be a bad crystal. So is it really? Should I do something so it won’t be a bad stone? I keep selenite next to it so it will be clean.