"Just relax" is one of my most hated phrases as well. I think it come from growing up in an environment where my brother and father would make fun of me and I would get upset about it. And then I was supposed to "just relax".
And you're right, if I could relax, I would. Telling people to relax does pretty much the opposite. It's dismissive and belittling.
- Natasha Tracy (bipolar and anxious)