Tough question
Excuse me for asking this but..... if he doesnt contribute equally to your existence, why would you stay with him? Seriously, this is a HUGE RED FLAG!!
I know because I have been USED in the same way by several supposed girlfriends. One convinced me that I was supposed to buy food for dinner every night, buy her beer every night and even supply her with weed! What a DAMN FOOL I was!! After I ended the relationship, she bought a new car!!
It sure sounds to me like he is using you in a big way and I dont blame you for wanting some proof that he is not snorting his money away. You are NOT CRAZY!
A healthy relationship starts with sharing responsibility for the household bills and if he does not contribute ANYTHING, something is not right.....