Jesus Christ, all the people telling OP to quit being a pussy and fend for himself. The problem seems to be that he's between a rock and a hard place. There's no money coming in for necessities, it's not going to magically fall out of his ass, and his mom (the house's primary breadwinner) has decided to fuck off and try to be a kid again.
OP, talk to her. Tell her you get that she's gone thru a lot and she wants to stretch her (newly unbound) legs, but that she still has responsibilities. Tell her you'll help as much as you possibly can, but she has to meet you halfway. Remind her that you're her son, that you love her very much, and that you're still a team--but she needs to help keep that team together because it's falling apart.
Good luck, man.