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I’ve been dating this guy for a few months now. We get along great and lot of fun together. He has baggage (going through divorce, has a kid, lives with friend), I do not. Found him posted on my local “are we dating the same guy” and found out he’s sleeping with others.
He apologized that I saw that and said he’s dating around.
We weren’t exclusive, but I assumed I was the only one he’s sleeping with.
He said he hasn’t felt this way about anyone else and wants to go exclusive now.

Do I have a right to be mad about this? Is this normal? I feel like if he’s able to be with someone else already, how can I expect him to be faithful long term?