I'm from America but live in Australia and invited my good friend and ex boyfriend out to come stay with me rent free for up to a year on a visa. For some background, he was figuring out what he wanted to do with his life and had never traveled much. I told him that he could figure out his life and study for the MCAT anywhere, so he might as well come someplace beautiful and hang out with me. We had dated very seriously for 2 years about 6 years ago and we've been very close for the past 4 years. He got excited about spending time with me and exploring Australia and agreed to come out. We were just friends at the time, but were flirting heavily. We both knew it was a temporary situation since he couldn't stay here for more than a year, so we set some ground rules. We agreed to be exclusive while he was living with me, but that it wasn't going to be a forever thing. Basically, we said that if we were sleeping together, we weren't going to pursue other people. And I told him that we could either just be friends or we could be together, but I felt uncomfortable with him flirting with and sexting other women while sleeping with me. You can see where this is going. About 6 months into his staying with me, he's on his laptop and gets a sext from some girl. I'm sitting next to him so I see it and ask about it. He slams the laptop shut and denies anything. I get suspicious and press him for more info about her. He gets angry and says to mind my own business and it doesn't involve me. So, I, very shittily, look through his facebook messages one day when he left his laptop out and see that he's been flirting with several women the entire time he's been living with me, including with a girl who flew to my city to meet up with him. So he's been lying to me for 6 months. He knew I would not want to continue sleeping with him if i knew about his side chicks. So he hid them and continued to have sex and be romantic with me. But he swears he never had sex with anyone else, even the girl who saw him here. I tell him I never want to speak to him again and ask him to leave my place. I give him 2 weeks to make other arrangements. But it's hard because I know he doesn't have a lot of money and he will have to stay at an Airbnb or cheap hotel. And he has to book a flight back to America which will be expensive. So, I feel bad. For snooping and for kicking him out. He swears he never cheated on me, it was just flirting. But he knew I would have chosen to stop sleeping with him if I knew, and I feel like that decision was taken from me. I just feel disrespected and a little violated.

Also, he never paid rent or anything and my name is the only one on the lease if that helps. He paid me 100 bucks once for all the extra utilities, but that doesn't come close to covering it. It was just a gesture since he is kind of broke. He's a good guy otherwise. He just doesn't seem to respect me very much. But am I overreacting? Am I the asshole here?

TLDR: my ex boyfriend came to live with me in Australia from America. I snooped on his laptop after I saw that he received a sext and he acted shady. He's been flirting with many women. I gave him about 2 weeks to move out. He's pretty broke and it will cost him a lot to rent a place and buy a flight back to America.