The problem I'm having is we are at a great place right now.
really? it's so great that a coffee mug has you considering conspiracy theories and that she REALLY bought it for another guy? you think your wife would be so downright stupid as to have a gift meant for another man sent to your house along with a matching mug for your daughter? and leave the box in plain sight???
if you don't want the thing - regift.
but perhaps consider what it represents to you.