First, sorry about your little girl. I agree with Julirs, it would take more than a week for her to get into the shape she was in. Sounds like you got her from someone that didn't know what they were doing in the first place and gave you bad advice and an unhealthy chameleon. Don't be to hard on yourself. You tried to get help but it was too late.
Take some time and read threads on this site that have to do with care, enclosures, feeding, etc. Some members have some really good websites dedicated to the care and health of chameleons. When you've done that, and have questions, come on and ask. We'll help.
When you feel confident that you're ready and able to give it another go, I suggest buying from a reputable breeder. There are plenty here (check the site sponsors and so forth).