Hey man before I begin just a warning, I am on my phone so I may make a few grammatical errors here and there.
Ultimately I have been where you are. I went to school full ride, grants and what not, for three semesters and each semester would get worse and worse. It got so bad that my third semester I received an F, D, and two Cs. My fast food job was going well so I thought hey let me see where this takes me. I moved into management very quickly and talk was going around of me running my own store in a couple of years. However, I did not like that feeling of doing fast food for ever.
Soon I had to think long and hard about what I wanted to do, and like you I wanted to do something significant. I demoted and went back to school with much passion. Unfortunately I have been falling off again recently.
I decided that I am not going to repeat myself and not ask for help. So now I am seeing a counselor every couple of weeks to talk.
Moral of my story, and my advice to you, is find out what it is you want to do and find a way to accomplish it. Even if you have to take time off to reevaluate your goals. Note that it is a bit more difficult to readmit if you take time off but it is possible.
If you will not benefit financially, or for some other reason, try and fit in some time to counsel with someone. From what I know counseling is offered at most universities at no cost as it comes with tuition. A good rule of thumb I have is don't be afraid to ask for help. It sounds like your family is willing to help so ask to use a car one day, set up some time to speak to your professors, and discuss anything you and they could do to improve your grade. Lastly go see counseling, school can be overwhelming and the thought of looking to that was difficult, but based on the impression I got from mine was that many people, like you and I, get overwhelmed.
I strongly believe that if you had a strong drive before that it isn't gone completely, again I feel you and I have that in common. Since I have a strong drive when I came back I did exceptionally well, so I'm confident you will also.
Long story short, do what you feel you need to do, and ask for help when needed.
Like I said I'm on my phone so I may have some mistakes, or have missed something. Message me if you have anything else to ask. :)