Replying to Caught my gf cheatin, what do i do?

I've been dating this girl for a solid two months now. Her face is a solid 7/10, body 8/10, but her legs are easily a 9 so obviously I get protective. We've been having a lot of fun together, but recently things arn't going too hot.

I got suspicious that she might be cheating with this longtime friend of hers, Mike. Now Mike's this little manbun wearing fuck boy who she's been friends longer than I've known her. He's a total fucking tool who is constantly hugging her when he see's her and hugs her goodbye too, like wtf! I don't trust this asshole for a god damn second.

So the other night I got suspicious she might be with him cus she told me that she was "tired" and "going to bed" instead of coming over to my spot. I thought she might be lying so I went on google earth and did a little spying. I zoomed in on manbun's crappy apartment building saw her car parked in his driveway! But if you recall she told me she was home..... going to bed... This really gets a guy thinking huh?

So what should I do? I need some advice. She's 100% cheating?