Yes, people will leave sites they find boring (which is why bounce rate is such an important metric).
However:
Boring is a subjective term
That said, anyone could find any site boring.
The important question to ask anyone who thinks it is boring is "what do you believe makes it boring?"
What you might not have considered is the fact that your friend might not be the best person to ask this question to.
When designing for anything, the first thing you have to do is understand your target audience.
Is your friend part of that target audience? If not, then who is? Find out who they are and find out how it resonates with them.
The point of any good design is to engage the audience it was designed for; identify that as well as clearly define the purpose of the design and work from there.