What to do what to do

Boyfriend of not even a month yet slept with this girl about 8 years ago. (So he says) and she slides in my DMs and tells me to ask about her and is calling me all types of names. I kept it respectful and asked her woman to woman for evidence or proof but she said she’s not giving it to me....

He said she did the same thing to his kids mother...

I don’t feel like he’s done anything to me but I’m just not sure

What to do?🥺