sick all the time

Hi my mother was diagnosed cml leukemia the end of 2006 she received her chemo and remained very strong through out her treatment.  Then she was placed on gleevac for maintenance.  Well we mad it to the 1 yr. repot all was looking great and then 1 month later she became ill.  We though she had the flu and it turned out cancer returned although this time it is all with the phylidelphia chromosone.  untreated she had a few weeks to live and treated a few months.  She went and had visctistine which i was told is a form of chemo(not exactly sure).  While in the hospital she had a awful time with her bowls not functioning due to the meds.  She was in the hospital a couple of months and since she has be home they same her blood count is good, although every day she is sick, she cannot eat anything. Violently throughing up. She is unable to go out of the house walk or even get to her bed since it is upstairs.  She is in and out of hospitals weekly due to this problem they have tried several meds nothing is helping.  Iam so confused i don't know if it's the cancer or something else.  When i ask the nurses and doc they say they don't know.  Has anyone ever had or knew someone experiencing this?