I have a high fever this morning and have to go to work, so bear with me if I do not make much sense.
From the outside looking on, I think your wife is scared. She cares about you but is dealing with some major demons from the past. She fears that you will give up on her and leave her and cannot bear the idea.
So, and I know this does not make sense, but that is how we are wired, she is trying to push you away. It is a control issue: if she pushes you away it is her who is in control, not you. Still she gets the outcome she dreads (you leave/are more distant) but it is more bearable because it does not involve rejection of her: she is in control.
I'd see it as a positive that she actually talks to you so much about her fears... Patience is the key...
And now I got to go... If the fever would be go away...
"You don't throw a whole life away just 'cause it's banged up a little"
Tom Smith in "Seabiscuit"
