My therapist scoffed at/dismissed too many very basic things at the beginning, and it set a tone for the rest of my time with her. By the time I was able to bring those feelings up, and she was trying to fix the effects of her words, it was too late. There are a hundred things I don't feel comfortable talking to her about because she's a judgmental person who speaks without thinking.
She claims to be the "least judgmental person you'll ever meet in your entire life" (direct quote), but she says her inability to think before speaking has gotten her in trouble many times in her real life. I believe it. But her words in a real life context would not have hurt me as much as they did in the timed, impersonal context of therapy.