Some people...

This is part of a conversation that I've actually had with a customer today:

Cust: "I can't get my bluetooth headset working."
Me: "Is it paired with the device?"
Cust: "What do you mean 'paired'? Pear? That's a fruit to me. You'll have to explain it in layman's terms."
Me: "Does the device see the bluetooth?"
Cust: "What? What do you mean?!"
Here is where I go through the steps to create a pair or partnership between the device and the headset - during which the customer interjects with:

"I've done this already, I've gone through this. I told you that!"
Me: "Okay, but we need to do it again. I need to know if the problem with the headset occurs before or after the partnership is created."
Cust: "Its not the headset! Its just not working..."
Me: "So, the problem occurs when you try to use the headset? After the partnership is created?"
(I'm avoiding the use of the word 'pair', since it's obviously nothing more than a fruit.)
Cust: "Partnership? What do you mean by partnership? I don't think you understand me..."

he denied this fact and told me he's "just loud". Mind you, this is not a man who seems to have problems with speaking English and it didn't sound as if it were a second language for him...so, why he couldn't understand basic words we learn in elementary school, I don't know.
I'd ask a question, he'd tell me one thing. When I asked again for clarification..the answer was different, and he'd yell at me that I didn't understand. Oh yes, then there's the whole treating me like I'm the stupid one. Of course I don't understand when you keep changing your answers. Moron.
He started out loud, and throughout the call he got to the point of yelling at me (and his dog, which was barking in the background. I'm lucky though - he only swore at the dog). Of course, he denied this fact and told me he's "just loud".
I don't understand how people like this make it through daily life.