Personally, I think I was worthy of love and commitment before, and while I would do things differently, if the partner that married me, committed to me, had children with me, spent the first part of her life with me, and gave herself to me without reservation and regardless of my flaws...if SHE left, then how is a person with higher standards and more screening and more cautious to make a commitment and stronger boundaries willing to put up with less crap...how is THAT person going to put up with me?
The flaw I see in this argument is that you're accepting the premise that she left you because something was wrong with you.
All spouses who leave are going to blame the partner. And even if they don't, LBS will ask what's wrong so the WAS comes up with something.
I think what we can look at in ourselves is whether we have some really bad habits and/or if we didn't do what we should have done when the R showed signs of trouble, and try to change those habits and be sure to not let things slide in the future.
And always remember that you weren't the one who left.
M 16 yrs, WH62, P54 3 adult blended kids EA 11/13, BD1 6/14 PA fall 14, BD2 2/15 Piecing 2015, BD3 12/15 Separated 4/16 WH moved OW in 5/16 Divorced 6/15/17