Staying with a cancer patient

So i really dont know where to start this post from..

Sorry if it turns out to be long..

The thing is i live with my DH here in India. And we have a sick custom of taking care of our in-laws . I am totally okay with it generally. But at this time of my life.. When am pregnant for the first time and i need to take utmost care of myself.. My MIL burdened me with the responsibility of her mom.. I.e my grand MIL. Its tough for me indeed but i cant say anything on it to ILs n even DH. Everyone is very attached to our GMiL and so am i. She is now detected with cancer and am wondering if it will affect my pregnancy or my baby.

No harsh comments please.. A genuine advice by people who really have a knowledge will b appreciated.

Thanks in advance!