My wife wants to try something I never thought she would — what should I do?

My wife recently told me that she wants to try something that I honestly never imagined she would be interested in. It’s something that we normally keep private between the two of us, but she wants to involve one of my close friends and experience it together.

I’m honestly confused and don’t know how I should feel about it. I love my wife and don’t want to make a decision that could negatively affect our marriage.

I’m looking for advice: How should I approach this conversation with my wife? Should I consider her suggestion, or is involving a close friend likely to create problems in our marriage? What would you do in my situation?

TL;DR: My wife wants to involve one of my close friends in something that has always been private between us. I’m unsure how to feel about it and want advice on how to handle the situation.