The fear is easy. For me I didn't want to anger her because I felt like I would then be contributing to her leaving. Anything that pushed her away further, caused by me, I could feel it being a huge regret in the future . It's one thing to have your W leave and you powerless to do anything, but thought of making a mistake that pushes her fully out of reach is unbearable.
It's the mindset of us nice guys thinking if we do everything right we will get to that goal to reconcile. If we don't do something right its then our fault.
Accept what is, let go of what was, and have faith in what will be
