Neglected snakes are way too common. You can't save them all but I've taken or paid $20 for ten snakes this year. People won't read a book or a forum like this one to learn about the care of _____ pet. Under fed, no water, heat an 100's of other problems. Dad gets the kids a pet but the I-phone is more important. Craigs list is full of regrets. As for people surrendering pets to rescues. The ones that cared about the pet will. The others just see what they paid out.
Put some weight on the girl an she'll be a good pet.
Good luck!