Mikeinsmd said:
What gender is her boss?
Are they close in age?
Is her boss attractive?
Why don't you trust her?
Has she cheated before?
She didn't have to tell you the meetings were cancelled.
She didn't have to tell you they were going to the Grand Canyon.
Why are you seeking marital advice from total strangers?
These are all very good questions. As I see it, the 3 most important questions are:
What gender is her boss?
Has she cheated on you before?
If not, Why don't you trust her?
I agree that there are definate warning signs here but if your wife and her boss have a good working relationship it may be an innocent trip. If there have been no problems in the past, I would give her the benefit of the doubt.
If there have been problems in the past, you definately want to confront her about it. Keep in mind that confronting her may solve the problem and it may create new problems.
Whatever you decide to do, remember to keep the faith.