I think my bf is cheating on me

So my bf and I have been together a year and half. He’s my best friend and I love him so much. He’s been cheated on before and swore he’d never do the same. We were going through a realllllyyyyy rough patch but for the past two weeks things have been amazing. Until today... I decided to snoop. Idk bad idea. But I found some worrying things.

First was a message to an unsaved number which is actually a girl I kinda know through him. They were talking about a party I was not invited to (he made that clear) and how it was her birthday and he needed to practice his moves to which he replied 😂👅💦 and other flirty messages. I asked him about it and he said that was a laughing face and quickly left the texts

Then I mentioned his snapchats with girls he use to either have sex with or talk to. One in particular he had called (before we dated) a “sexy, hot, kinky goddess” and has been messaging up until 3 days ago. He lied and said he hasn’t messaged her in 3 years. But that’s not all. There are other flirty messages.

He says these girls message him and he doesn’t respond but Snapchat seems to say that they don’t respond to him. He refuses to talk about it and it’s breaking my heart. I don’t know what to do. Am I being crazy? Did he really not do anything?