Tired

I happened to mention to Bert that I was feeling tired. He said,

If you're tired all the time how do you know you are tired?

What do you mean?

Well. You're always going on about being tired. If that's the way you always are how would you know you are tired?

How often would you say I mention that I'm tired?

About once a day.

And roughly what time of the day would this be?

About this time.

So when I happen to mention, once a day, around 10pm, that I'm tired - that means I'm tired all the time? 

God's sake. You don't have to be so sensitive about it!

You know something? I think I'm in denial.