So you are worried that he will go out with his ex again after you two break up? I am confused. Why would you even care about what he does/did when he is not in a relationship with you.
I understand that you think he may not be over his ex or something, but the way I read this is that he didn't cheat or anything. Maybe his first ex was a rebound from his second ex. And if so, so what? As long as he isn't cheating or anything, I just don't get it.
If you feel jealous and worried, you need to ask yourself why? Are you jealous because you are insecure yourself or has he done anything during your current relationship to make you feel that way?
Good luck.
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