Baby & cat

I know when you have a newborn you have to keep the cat out of the bedroom so it doesn't sleep on baby's face. I'm only 6weeks but have a cat & she's so demanding to be in the bedroom, I know if I tried to shut her out she would just meow constantly at the door. She sleeps in bed with us every night. How did you mums deal with this who have a cat and baby? How long do they have to be away from baby for? Till the baby is how old?