should I be worried or

i found out the guy I’m with cheated on his ex multiple times and was apparently very mean to her. Hearing this really surprised me because he’s literally never mean to me, he’s actually the sweetest guy I’ve been with. I also couldn’t believe that he apparently cheated on her MULTIPLE TIMES because his ex is gorgeous. she’s literally my girl crush. I don’t know if I should ask him about it or not because I’m not sure if it’s my place but it’s been bothering me SO MUCH.