it sounds to me like everything you two went through together was just too much "baggage" in the end. and especially the loss of a child must be incredibly traumatic, for both of you. maybe she just couldn't take being reminded of that loss anymore. (i'm so sorry about your loss.) maybe she felt she needed a fresh start. leave all that behind.

all those are just guesses, of course there is no way for me to know the reason for what she did.

it does sound like you need some professional help, like you need help getting through the grieving process. do you have a therapist? or is there any way you could find one?