Baby daddy issues

Ladies advice? So I’m a female (25) baby daddy is (29) going on 30 this year, we have a 4 year old son. We were together for 5 years but we split up May 2024. And then he tried getting back with me like a month later & we were trying but ultimately didn’t work out. The last time him and I had sex was November 27th. And that was pretty much where we just left things off. Anyways, it was hard to let go but ultimately I had to just work on myself and focus on my son instead of keeping my hopes up. Long story short, we had been coparenting just fine. And last week, we took our son to Disney for his birthday. And his dad was all over me tickling me, play fighting, complimenting me, wanting to buy me gifts, and just flirting the whole day there. Then, we get to my parents house bc that’s where I stay with my son, and his dad and I lay down and watch a movie w our son and we just start kissing and hugging right in front of him and he pretty much started it and I went along with it obviously bc I still love him. Anyways, he goes home that night and then I text him this the next day and this was his response… and yesterday (Saturday the 8th) someone who follows him on IG showed me a picture he posted where he’s out eating with another girl. Who I believe he is talking to.