Numerous Medical Conditions plus recurring BC

We just learned that my mother has recurring BC for the second time.  I have not learned as much about her bc as I should have at this point since we have been fighting this same cancer for 3 years now.  Due to her other serious condtions, this 'cancer thing' has sort of taken a back seat.  She has End Stage Renal Disease (kidney disease) and is on dialysis which complicates things greatly.  We have been dealing with so many different conditions for the past 8 years that this just seems like the next bump in the road, only this has become more and more scary.  Obviously it's not that simple.

We are now facing another biopsy on July 7th to confirm if this is a recurrance of her breast cancer or something new altogether.  We just got the results back of her latest scans and discovered that she has 4 new tumors, 3 of which were not there in March. The good news...it appears that it has not spread beyond the left chest wall and neck. 

I have been my mother's caregiver for the past 7 years due to all of her illnesses.  Not sure how much more her body can take.  However, she is truly an inspiration, as she just takes everything in stride.  She has the best attitude for someone with her ailments that I have ever seen.  She is simply a wonderful example.  

This time I'm more scared.  I guess what I am looking for, is to find out what questions I need to be asking of her doctors.  You'd think that since we've been dealing with this for 3 years, I would know by now.  Her treatments have been complicated because she can't just take any treatment for the cancer.  She must have medications that don't need the kidneys since they don't function. 

I have been so focused on her other ailments that I have not been diligent enough aobout the bc since the ONC has been positive to this point.  I need some guidance as to where to go from here.  I don't want to let her down by not knowing the right questions to ask.  Does anyone have any suggestions??? Please help.