...your friend has the same item of clothing?

This is an etiquette question.

You wear a great dress.
A friend compliments you, asks you where you got it.
You thank your friend, and tell her where you got it.
Friend goes and buys it (remember, imitation is the greatest form of flattery!). She may or may not tell you.
You find yourself at the same event with friend, both wearing the dress.

Awkward.

What's the appropriate etiquette here?  I can only answer from experience.

Lisa and I have MANY of the same pieces of clothing in our closets.  A Marc by Marc Jacobs blouse, a Vince sequined top, rag & bone booties, etc.  We almost always consult each other before this type of purchase,  a "I love those booties!  Do you mind if I get them too?" conversation.

Then, when it comes time to wear the item, this is what we do (more or less):

The person who found the dress has 'priority' (Person A).  If the 2nd purchaser (Person B) wants to wear the dress to an event to be attended by both A and B, B needs to contact A to check to see if A is wearing the dress or not.  If not, B is free to wear it.  If so, B needs to find another outfit.

Had Lisa and I not done this, we would have worn this same Vince sequin top to a holiday party, over black pants:

Photo from shopbop.com

What are your thoughts on how to handle this? ~ JH