Once a cheater always a cheater?
What Guys Said 1
It is almost certain that he is going to continue this pattern. I would tell you to tell the other girl about his infidelity if you two know each other. If you two don't know each other, then that conversation could be awkward and, if she takes it the wrong way (you're trying to get back with him because you're desperate), it could cause unnecessary tension between you two.
This is my thoughts, but if anyone else disagrees, please say so.
What Girls Said 1
He will definitely cheat on her, no question there.However, I don't think you should warn her. I mean, he's your ex now, problems between him and his new girlfriend are between them. I think you should stay out of it.
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