Sometimes it is the other person's right to be "wrong". Obviously their reaction or attitude is right for them. Unless they are your child living in your house, you cant really set the rules for them. I think this is the distinction your t is trying to make.

Its not about taking your side in this argument, or trying to prove the other person wrong, or change their mind. Its about, given that the other person has this attitude, how are you going to live with it?

Altho i think they could make that more clear. Maybe they do and i couldnt stand to hear it. Albert Ellis certainly did in his RET, and i hated his attitude.