Mother caring for daughter with breast cancer

My 30 year old daughter was diagnosed with breast cancer in July, has since had mastectomy and chemotherapy.  She is having her other breast removed this February.  I do not live in her city so moved in with her and her husband and baby for four and a half months so I could take care of the baby and do household chores so her husband could work.  I love my daughter but I have found this time very difficult as she has been very short with me and angry.  (Not all the time as we have also had good times as well). 

I held my tongue so many times but inwardly felt very lonely and sad.  I tried to ask my daughter not to be rude to me but usually got the same reply.

I really struggle with feeling guilty that I could not be a saint and never feel down or angry with her given that she is and has been through all that she has. 

Any thoughts for me to cope when I go back to stay soon?

I see that your post was in January so you may have solved your issue.  I have no real advice but wanted to tell yu that I am also caring for a 30 year old daughter, infant son, and husband while she is receiving chemo.  I know exactly how you feel because I am feeling exactly the same way.  Also, I know exactly how your daughter is treating you because mine is the same way toward me.  I console myself by telling myself that I am a safe place for her to vent her rage.  I understand this intellectually but it still hurts emotionally.  I'm sorry that I can't offer words of advice but I thought it might help to know that there is someone else out there going through the same thing and that what we're going through is probablay the norm.