Difficult choice, i need major help?

get rid of the girl. she made the decision to lie to you first and had with him. At least he was honest enough to tell you. And he feels guilty enough that he is afraid to hurt you again, therefore, in his mind, the rational thing is to let you go. trust me. it hurts alot to let someone you love go. especially if they **** up. but it hurts enough worse to know they were honest about it and you still got rid of them.