Did you meet the same situations like me?

My mother has one chronic disease, and feels very bad, even though taking medicines everyday. If she does not wait to see me, she will stop taking medicines.
Now I do not know when I should go back to China, because once I go back and see her, she will not take medicine and pass away very soon. However, If I go back late, I am afraid I can not see my mother again.
It is very very hard to decide when I should go back.