This is roughly what I tell myself in those situations: "I'm genuinely not interested in what this person is saying and it's not my job to be magnanimous about it, nor do I need to be rude. I cannot manufacture interests. I do not need to get along with or be friends with everyone. I have friends and I am interested in the things they say." Owning the truth of how you feel, regardless of its effect on others, is immensely powerful.

You honestly don't sound like you have the problem I was asking about: compulsive meanness.