His baby mama just pops up. At what point do I say f*** it?

The dude I been messing around with baby mama just pops up at his family’s house (his mom and aunt lives across the street) when she wants to. I don’t know if she knows I’m across the street at my grandparents house. I have seen her call him at night and he ignores it. He says they are done but I have a hard time believing that. She texts him all the time and I do try to be nosey to see what it’s about and it’s always about their 11 month old baby. And I hardly see him text back. Yesterday she drops the baby off and she had to come back and get her not even an hour later because he lied to her about why she had to come get the baby when I was the reason why she had to leave