Sure you have.  Which means that you just said that because you want to tell me what you lied to me about twenty years ago.
I haven't lied to you in 20 years.
Is that why you think I'm here? That's why you're here. That's why you're lying to me about!
Is that why you think I'm here? That's why you're here. That's why you're lying to me about! [SEP] I haven't lied to you in 20 years. [SEP] Sure you have.  Which means that you just said that because you want to tell me what you lied to me about twenty years ago.