I would recommend that you don’t speak to Bob.
I think he’s shady and not to be trusted. If you say "hey Bob I’m not comfortable with XYZ between my wife and you", he will see you as insecure or possibly sense a divide in your marriage. And that may give him a chance to act if he thinks there is an opportunity with your wife.
I used to watch women openly flirts with my H. I didn’t care. I wasn’t jealous.
Now? If it happened my H would get a "look" from me and that might mean anything from "dial it back" or "get rid of her".
It doesn’t happen now because my H is very aware of boundaries and what is acceptable behavior.
But it wasn’t until I asserted myself on dday2 that anything changed.
Honestly I had the it’s "her or me" conversation b/c I was prepared for the outcome. You hope it doesn’t come to that but to get what you need, it may have to happen.
And if someone who is a business "colleague" said hello beautiful to me, I would think he’s a complete jerk and would reconsider wanting to go business with someone who shows a complete lack of professionalism.
Believe me I have my business built on relationships. I know how to make money by being charming. But it NEVER is unprofessional.
Long and short - Bob is a problem and your wife needs to do something about it.
