WTF is the deal with people who are contrary conversationalists?

I once worked with a woman whose conversational style was to disagree with everything I said. One day she remarked, "It's a nice day outside." I said, "Yes, it is." She said, "Not really. It's kind of crappy outside."

I don't think she was even aware of her behavior.

I've come across other people like this before, but I never thought much about it until I read this post by Gretchen Rubin, author of The Happiness Project:

Here’s a new phenomenon I’ve tentatively identified: oppositional conversational style.

A person with oppositional conversational style is a person who, in conversation, disagrees with and corrects whatever you say. He or she may do this in a friendly way, or a belligerent way, but this person frames remarks in opposition to whatever you venture.

I noticed this for the first time in a conversation with a guy a few months ago. We were talking about social media, and before long, I realized that whatever I’d say, he’d disagree with me. If I said, “X is important,” he’d say, “No, actually, Y is important.” For two hours. And I could tell that if I’d said, “Y is important,” he would’ve argued for X. I saw this style again, in a chat with friend’s wife who, no matter what casual remark I made, would disagree. “That sounds fun,” I observed. “No, not at all,” she answered. “That must have been really difficult,” I said. “No, for someone like me, it’s no problem,” she answered. Etc.

Since those conversations, I’ve noticed this phenomenon several times.

Over 190 have commented about this on Gretchen's site.

Ever Been Stuck in an “I’m Right; You’re Wrong” Conversation?