Ooooo - you missed the best bit MM.
I've just watched it this morning but can't quite remember the sequence of events at the end.
I think you probably saw the bit where the horrible man and his family were at home and the wife told the daughter (can't remember any names, sorry) that she would be leaving for her school in Switzerland early and they wouldn't expect her back for holidays and that she would be almost 18 when she finished so "I'm sure you understand what I mean".
He left his house and step mum hugged him and said that if you write, write to the London flat as we are leaving here. He said that he wouldn't be keeping in touch and he left to go to the railway station. Then the girl turned up (the one who had been beaten) at the door and step mum told her that he had left so she ran to the station. She got there just as the train was coming and she told him that she was going to school in Switzerland and that they could keep in touch. He gave her the address he had been billeted to and said that he didn't know where he would be after that but he would come to Switzerland to find her. They told each other that they loved each other and they kissed and he got on the train and they kept kissing until it pulled away. Then in all the steam she stood on the platform with her arms outstretched shouting "we're safe now" as the train pulled away.
Am loving this drama.