Emergency medical help for Tillie

My name is Ally, and if you know me well, or even just through social media or around town, you'd know I post photos of my dogs hourly. I miss them when I am not home, talk about them with whoever I am with, and overall they are my best friends and have brightened up my life in a way I can't explain.
Now, Tillie? She's special. When I went to a shelter a year and a half ago, I did not plan to come home with ANOTHER pup. But something happened when I saw Tillie. I was told she was part of a shipment of more than 1,500 puppies who had been lost/left behind from the hurricane in Puerto Rico. Taking her home with me was the best decision I could have made. She became a mama's girl immediately and I fell in love. Tillie fit right in with my other animals and made herself at home with us. Her unconditional love has carried me through many of my life's struggles over her time with me.
Friday September 28th something unthinkable happened. I got a call from my frantic mother telling me Tillie got hit by a car on route 33, which being a highway, cars are flying by at high speeds. I originally thought without knowing details, I had lost her. My mother rushed her to the nearest vet where I met them. I was told she could be saved but would need a highly expensive surgery for her multiple and critical wounds. I used every last penny I had along with some help because they would not lift a finger until I provided the money. Tillie was hit on the rear and dragged for a short time. The damage skinned her exposing her internal muscles and a gaping hole, stitches are not fixing the problem.
I'd do anything for my dogs and I feel entirely helpless. I've come to find out she is going to need additional surgeries and treatment. I work as hard as I can to make ends meet and can not afford additional treatment. I am also becoming a full time nursing student making it even less possible for me to afford this cost while working even less. When I told this to the vet, they simply sent me on my way. I asked them what they would do if this was their baby?.. the response was minimally emotional as I am sure I am not the first to be in this situation and they can not help everyone.
Up to date, her wounds are swollen, she is shaking, not eating and not going outside. I am beside myself even thinking about leaving Tillie in the condition she is in. They have charged me for each bandage change and visit. I am humbly asking for help hoping that there are other people out there that looks at their pets as their children (I'm slightly obsessed with my animals). I understand the entire cost is high, but anything can help. A simple donation could cover the cost of a check up or bandage changes. It is not easy for me to ask for help in this way, but this is my last opportunity to be able to help my pup. The vet refused to re-stitch her or re-bandage her at this point. My tears haven't stopped. I have asked if there are any charities, and reached out to friends in the field. I am not doing nothing, but feel I can not do enough. I can not imagine my life without Tillie, she is a young fun loving affectionate puppy, and the look in her eye is mortifying.