Why does my ex keep coming back?

my ex has 2 kids by a woman that he’s off and on with. before he had this new family i was the ex right before the first kid. he keeps coming back … sometimes he will flirt with me , other times he seems to want to work with me on his business projects he has … i can’t tell what he’s looking for? he says he wants to be “friends” but he is my ex … and he has a family ….. by a woman who doesn’t like me …. he’s been coming back every other year since 2020 … why? desperate? he is also a long distance ex so this is all via social media and facetime. we hung out a lot in 2020 but after his family , it’s just over the phone conversation. why is this?
Why does my ex keep coming back?
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