hmmz.. are you still in the "mood swing" mode? if it is then try to calm down first, and wait till it go off then decide more clearly. since you living with your in-laws, you have little choice of choosing to stay at your mum's place and not going back, as it doesn't sound right.
and by the way, you applied for a flat, if yes, then maybe you can just endure with it and stay in you in-laws house until you get the keys.
or althernatively, you and your hubby can sit down and discuss the responsibilties of taking care of baby.. what i mean here is rotating the baby between your mum and your in-laws.. that's what i did..
since my father in law is a smoker, i told my hubby that no way, will i let baby expose to 2nd hand smoke.. so i sat down n discuss with hubby that if both of us not at home (coz hubby working shift), baby will be bring over to my mum's place, and if either of us at home, baby will be at in-laws house since i'm staying with them. i hope i'm not being confusing here..
and anyway, like you, i also like baby to be taken care by my mum, but i know thers's little chance that it worked, as i'm staying with in-laws, and i got to show them some respect, and also think of my hubby.. so no choice, i rotate my poor baby around ..
you can consider this suggestion.. but provided that your hubby understands your situation well..