I think he got a free pass because even though he picked other girls, he always maintained a bit of distance from them. With Kaz, he said he wanted to take it slow. With Abi, he told her he needed time to get over Chloe, and with Mary they were hardly together. Also he always talked about Chloe - I remember him saying that if it were Chloe rather than Abi he'd never have picked Mary. And I think that's why the girls all forgave him, because he didn't really get too deep with them.