If he always hangs out with you. If he sticks up 4 you.
Does he flirt with other girls if he does then he is unfaithful. If he doesn't u got someone you can trust.
First of all if you have to ask the question the cheating has already happened. Trust your own instinct if you believe that he or she is being unfaithfull the they probably are. Also if they have cheated before even if it was with you on a previous girlfriend or girlfriend once a cheater always a cheater.
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