What happened here is she is damaged and unable to bond. It has NOTHING to do with you or anything you did or didn't do. Sure you probably could have kept things going longer if you didn't push so hard, but be clear, this girl was NEVER going to develop "feels" for you or want a 'relationship' with you.
Why are you taking this so personally? Look at her HISTORY! 35 and never had a relationship besides fwb, that is important information you should have paid attention to. Nothing to do with you.
Stop trying to save women and thinking yuu have some special power to turn a damaged woman unable to bond into a loving caring nurturing woman who will love you forever. That's delusional thinking.
Next time a girl says something like that to you, make the decision to keep her as a plate only, do NOT get invested and don't even think about having a relationship with her let alone a serious one.
Lastly, you are 41, figure out why it is you continue to fall for damaged women like this and unable to move on after it ends.
This indicates you are also damaged in some way.