if he's the kind of guy who would secretly kill you then you've got to get the fuck out of there.

if he try and cut him out as the middle man and take over the money situation he could get pissed off and kill you for money.

if you just pay it yourself then he's going to keep stealing money and expecting you to bail everyone out.

im guessing it's not really easy for you to move out on your own though.
what's the situation with your parents?