9 “Triggers” That Can Make a Guy Suspect an Affair, Even If It’s Groundless

6. She travels on the way home with a colleague who goes in the same direction.

“I think he actually thought, ‘If you go home the same way, you should take a different train.’” Some guys get suspicious of their girlfriend’s relationship with a male colleague if they take the same train or bus home. If your boyfriend is making a fuss, let him know beforehand that you’ll be traveling with a colleague.