CO-Worker thinks I made her look bad and screwed her over..HELP!?

Look, from what you said shes a slacker and doesnt take her job seriously, You did a good job and got what you deserved by getting the money for that job. You cant cover for her every time she is away or slacks off or whatever. You did good work and got what you deserved and your management is already upset with her so even if you show them this "proof" she had something to do with this deal they wont do anything because you made it possible.