Sorry for your bad experience! The most important part of what you plan to do now will rely on your contract. Did you work through a recruitment agency? Do you have a contract? Read our page on work permits for Abu Dhabi for some extra information.
If you worked through an agency, they should be able to advise you as to what to do. If you didn't, you need to make sure that you haven't been a victim of the current black-market of Filipina domestic workers. Your employers shouldn't keep your passport, and if they do, it's a definite red flag. The UAE has plans to protect the rights of domestic workers, but at the moment, it is a murky area. This article discusses what the UAE is planning to implement.
Do you have a copy of your contract?