"Why I even fight for her anymore I don't know..."
I have a theory that as the situation continues without positive progress, there comes a point in which the LBS becomes the WAS.
I believe you have to take a break from pursuing and from trying to win her back, and not only fix yourself, but take time to consider what the R would be like if she suddenly changed her mind and dropped OM and came back.
Would you be able to get past her transgressions? could you truly forgive? and not hold it over her head?
I know, for me, even while i was pursuing, and trying to save the marriage, i also realized i could not.
"In a ham and eggs breakfast, the hen is involved, but the pig is committed".