One thing after the other 🥲?

So as some of you know I'm currently pregnant, I don't know what to do with my baby's father that I'm currently with.
I just seen asked him to open up a conversation on his game app and it was with another girl. 💔

She said: awesome chat background
He said: thanks
She said: I may have to send you whatever messages just to be in here!
He sent an emoji of a guy getting his face slapped.
She said: lol who are you slapping
He said: you slapped me
She said : 😂😂😂 are you drunk? Hahaha
She said: did you just slap yourself?
He sent: na I have evidence that you did
She said: let's see them? The cheeks?
He said: emoji with a blushing face, I asked him what he meant and he said it's like saying you're a liar ffs
She then finished with: you're funny but no one will believe you. bee never slaps without good reason, hahaha

Is this not totally understably inappropriate?
We've been together three years, I just feel like wtf man
Updates
8 mo
He then twists it on to me and says I'm over reacting and the conversations normal 🥲
One thing after the other 🥲?
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