No way! You're not being overly sensitive. His friend needs to go.
A promise is a promise and he needs to keep it!
I'm different about the shopping ,I don't like it when my husband wants to go shopping with me. We fight, complain, he doesn't understand how I shop. He snickers at me behind my back for no reason ... lets see, He buys everything he sees, I think about things. And the kicker is HE WANTS to go with with me.. so I go when he's not here, then I can go by myself. hehehe.