Using a prop from one show for another after saying people shouldn't touch them (it's not your prop for the show you're SMing- keep them separate!) was probably not a great choice. And being passive-aggressive about other props afterwards? It doesn't exactly make you look MORE professional. But it happens to the best of us! Stage managers have feelings too.
I try to stay calm, collected, stern but friendly. As you probably know, being nicer can get you much further than barking orders, so I hold onto that as much as I can. Project firm but friendly and then complain on the phone to your friend.

Taking a step out of the room for a minute or so can help, and after rehearsal or on a break (give everyone time to cool down!) pull him/her aside and talk about it. One-on-one discussions are definitely better than a confrontation in a room full of people.