Given you history of academic difficulties, I would not recommend taking a second job to pay for school. I have seen time and time again that the students who struggle most with school are the ones who spend too much time working. I took out student loans for both of my undergraduate degrees, but it paid off because my higher grades qualified me for scholarships and helped me to land better jobs once out of school.
Remember, if you can't pass through the nursing program because you're working too much and graduation is delayed yet again, you will be not only be losing tuition money, but you will also losing out on the higher income that you could have been earning as a nurse. This is called opportunity cost.
Federal student loans do not require a co-signer. However, because of your age you will have to submit your parents' financial information on your FAFSA (Free Application for Student Aid). http://www.fafsa.ed.gov
Depending on your parents' income and assets, you may not be able to qualify for grants or subsidized loans (unsubsidized Stafford or Direct loans are easier to obtain). Parental PLUS loans require a parental co-signer, so they may not be an option for you.
Strongly consider what your parents have to say when they state that they will no longer support your schooling. What is their rationale, and is there any way that you can earn back their trust? Having them in your corner for emotional support (if not financial support) during nursing school could be very beneficial.
If you parents truly do not financially support you in any way, you can contact your school's financial aid officer to find out how to be declared independent for the purposes of financial aid. However, they have made this more difficult in recent years so even if your parents don't give you a dime you may not be able to omit their information from your FAFSA Here is the federal eligibility worksheet. http://www.finaid.org/calculators/dependency.phtml
If all else fails, you may be able to find another relative (grandparent, aunt, uncle, etc) who is willing to co-sign for a private student loan.
Good luck with your plans. There are many of us who made it through school with no parental financial support (in my case, my mother did buy me food and necessities from time to time, for which I am grateful). You may find in the end that you are a stronger person for the struggles that you have endured at a young age.