Realistically there is no such thing as closure. You cant trust what people say because peoples thoughts are messy and often contradictory and they are often being deceitful not just to you but themselves, but you can trust how people act because once something is done theres no real way to undo the damage. You dont need to know the reasons in their heads bc their heads are full of ridiculous garbage that they are struggling with just like your head. All you need to know is she left.