Hi Primal pain, Illegal toilet,
I have failed assignments on my courses, while unwell/to tired etc. yes it hurts like hell, I was able to Re-take many courses let you do this. Discuss with the school, college, Uni to see options available. Use tutor support, as often they will check that you are on the right lines with assignment. Libraries at uni's often offer tailored support to help with writing assignments etc. Some offer more help for those with learning difficulties.
Look at courses, some have a more practical element which will help grades.

It is not to late to get a degree, just explain you wanted to improve yourself. Which most employers really do appreciate. Not everyone has a degree, go for it if you really want to.
Good luck both of you.
Take care
Kate