I'm sorry you are both experiencing this awful situation. I am sure it causes feelings of helplessness. I  think you sound like a very caring person.. 

Obviously I do not know either of you and do not know if the pain you refer to is physical,mental or both but it must be remembered  that cancer diagnosis, treatments and surgeries  are invasive. (Physically  and mentally)

that alone can have an effect . You mention breast reconstruction. Society brainwashing foolishly turns breast  into 'femininity ' 'attractive ' etc. Is it this feeling of loss of parr of her body in relation to that?

Is she having cancer counselling? I think that would be helpful as there is so much physical and mental trauma when dealing with cancer.

So much will have happened to her that she might be struggling to process it. Which is understandable.

Sorry if my reply is clumsy and I  hope things get better for you bo you both. 

Kind regards

Perhaps it is something she can look into when she feels able to.

A support group of those who have been through  similar Perhaps? 

People DO need a safe place to vent

She may be dealing with clinical depression which would not be surprising given all she has endured  ..does she have a helpful supportive GP that she can confide in?

The bottom line is you asked what you can do.. and beyond suggesting counselling and being patient it sounds like you are being caring and supportive which is a huge positive.

I don't come to this website often but hopefully others can offer better advice or suggestions. 

Oh and 2 more suggestions: :

1) as someone who has been on both sides of cancer  in past (as the Worried About Someone With Cancer  person  and as the Bloody Hell I Got Diagnosed With Cancer person) I would suggest you look into cancer counselling  for YOURSELF too. 

2) perhaps you could call the help number for here or Macmillan 

All best

Thank you RadioGirl x