Mine used to be. Any little mistake I made I would call myself stupid and incompetent. I would also run scenarios in my head about what I THOUGHT someone said about me and how awful they were, and worse.
This happened so often that these became the only thoughts I had about myself and others. When I started having some self-awareness about this in my 30s (I'm definitely a late bloomer to self-awareness) and I heard my inner voice go on and on, I would think STOP IT. And sometimes I would even say it out loud-STOP IT! (of course when no one was around).
I realized that I would never talk to a friend the way I talked to myself so I started treating myself like I would treat a friend. After thinking STOP IT I would change it to, "Oh sweetie we screwed up didn't we" or, "Sweetie knock it off-this person isn't even thinking about you or how they treated you, use this brain to think about something else".
It wasn't until I had quelled this mean-girl inner voice that I started to notice that I heard what would eventually to be known to me as a spirit guide. And once I acknowledged one or two, I heard from more and more. Their voices are kind and sometimes sarcastic but never mean, always loving.
Having awareness doesn't mean I no longer have mean thoughts about myself and others. What it does mean is that I notice it quicker and shut it down quicker. I've also learned to question myself, why am I thinking this way? Am I scared, embarrassed, angry, not getting my way? My answers to these allow me to deal with what is really going on.
Are you mean to yourself?