Hmm.
As a teaching student, I have heard muchos stories of young kids watching their even younger siblings because their moms are single moms working two and three jobs. While during the school year it makes it really hard on these kids, they don't have a choice. But hardly anyone seems to realize that this sort of thing happens all the time in the inner cities or in low income housing, so WHY wouldn't we think it could happen to "us"?
I would say that 12 years old is old enough to babysit. That is the age when I began to babysit neighbor kids. An hour and half is not much time to be alone anyway, and if you have taught your children responsibility along with the important emergency procedures they should be fine. However, I would suggest finding a different babysitter, even if you love the one you have, because $10/hour for babysitting is MORE than I make at my full time job as an adult. I pay my babysitter $25 for a full day, which is still $125 a week, which is comparable to day care.
I have to say as also being a single mom, I would NEVER allow my home to go to forclosure. Doing that would cause me even more stress and cause my son even more stress having to get tossed out of his home and comfort zone. Also it would ruin my credit, making it even more difficult to survive in the harsh world later on. As forclosures are rampant in my state, and having watched a close family member go through one, they are a nightmare. My famiily member is now being sued by the mortgage company TWO YEARS after the forclosure. He is facing bankruptcy and his kids are suffereing for it.
How many of us had moms that worked? How many of us had to stay home alone while our moms worked? I know I did. I know I turned out ok. What is important is that you are still a family and that you still love each other. Kids CAN understand why Mom has to work and your kids are definitely old enough to participate in family discussions and have a say in what is going on too.
Don't quit your job. Your "only" $15 an hour job would save my life right now. Like I said, I make less than $10. And I am lucky to have even that here in my state, where it seems half of everyone is unemployed and without health insurance.
Don't let others pressure you into anything. These are your kids and this is your life and you make the decisions, right or wrong. You are doing the best you can.