How would you take this?

I have a business partner, we used to work for the same guy a few years ago.

We've always kept in contact with this guy and now he's arranged for us to have a meeting with his new company to discuss possibly getting a contract with them.

He asked me to prepare a slide deck on our company, which I did. I worked until almost 22:00 that night working on it.

The next morning I sent it to him, he said it looked great... And then said my business partner (who honestly does not know as much as I do) to do the actual presenting. In fact on the original email invite, I wasn't even included. My business partner asked them to include me.

I feel a big disgruntled about that to be honest. I don't have confidence my coworker will present effectively, because in most of our meetings I end up doing most of the talking because she doesn't know as much. I feel a bit insulted, to be honest.

But at the same time, I think maybe he told her to present because he knows I'm already doing most of the work.

Am I being sensitive?