I've talked a lot about cognitive distortions in my therapy.

It's not that what I think isn't real... it's more that the way I think things is hurting myself and is making my life hard. I have a really strong tendency to think I "know" what other people are thinking. And it is usually bad stuff. However, I don't actually know what people are thinking, and this pattern really hurts me.

I think reading The Feeling Good Handbook by David Burns has really helped me.