Upset when ex talks to other girls

My ex texts girls in front of me and he even took a phone call in the bathroom and lied about it . We’re not together but he was over because he was visiting our kids and we were taking our toddler to the dentist. He also texted so much at the appointment. I know i have no right at all to be sad or upset about it but i do. We have sex a lot and now that he’s talking to other girls i don’t know what to do . We both still love each other but we know theres no getting back together. I don’t want to be with him because he’s a cheat. I don’t know when this will end I feel stuck because i still love him so much and it’s been a long time since we’ve broken up. I’ve talked to other guys but I can’t stop loving my ex. 😭 ladies what did you do to get over an ex?