If you're struggling in life to make a living are your parents supposed to help you? What is supposed to happen?

It's nice if they can but if you're an adult there's no law that says they have to.

Of course parents will help when they can, that normally depends on their circumstances, the help required and how many times this child has been helped out in the past.

A parent would not really be doing their job if they repeatedly kept on bailing an adult child out. Children living beyond their means, feeding addictions et cetera

Once you reach 18, parents are free of responsibility for you

Some do. Some don't. It all depends upon their financial condition and yours. My parents would have helped me, of that I'm certain. I never placed them in that position. However, I do help my kids from time to time. THEY DON'T ask for it.