Gosh what a terrible predicament to be in, I honestly have no real sound advice here either.

I knew of a family that were like that when I was at High School, and like you said, they were grubby, but loved and hey they made it, unfortunately they got hell from other kids and called awful names, so I felt real sorry for them.

Their lifestyle sounds pretty disgusting to me, I don't think I could handle it myself, I cannot bear kid's with a dirty face even, and stained clothing, but if you can well good on you.