Can we have this conversation?

Do you have conversations with your friends, family, significant others that get heated? Are there topics you can or can't discuss? It is your communication style that is the issue, or the topic you are discussing? Is it when, how, why, and with whom you have the conversation.
I am not scared of an intense conversation. I enjoy debating. But you know when you hit the point in a conversation that it has gone too far or hit a nerve.
I have discovered the most challenging subjects aren't always the usual suspects, what pushes your buttons? Pushes their buttons...