My roommate invited a guest to live with us

So about two weeks ago, my roommate mentioned that a guy she met off the internet would be coming to town but that he wouldn't be able to afford to stay in a motel. She asked if he could stay with us to which I said I would think about it but that I really wasn't comfortable about the idea.

She didn't mention it again for weeks, but the other day she said "You know blank is coming here today, right?". Without permission, she had invited him to live with us for over a week and only gave me an hour of notice before he was to arrive. I am very uncomfortable with him being here, especially because she had never even met him in person before he showed up.

She ignored my text saying that her friend is not welcome, but she hasn't replied at all. She also spends all her time locked in her room with him, so I haven't been able to talk to her in person.

I already know she's going to make me out to be the one in the wrong, so.... Am I the asshole?

Edit: I told her I will be moving out and she'll have to figure it out 🎉