First of all i would if i were you, thank those that would ransack YOUR question for an argument, and to be quite honest, consider whether you are going to feel right when you are not with her, when some guy looks at her, or when you see, as they say, corresponding disasters every night on the TV.
I went through it, it hurt like hell for 21 years it made me bitter and unhappy towards her. You could leave and salvage something like friendship, stay and worry or just move on!