I need to vent..

SO! I have been employed at Animal Hospital of Pasco now for a little over a year.. I love my job and I absolutly love the people I work with, they are like family to me. BUT I am treated like a pile of dog shit by a few un-mentionables.. During my interview I was told that I would be a veterinary assistant and would be assisting.. I was lied to on so many different levels.. I am a dog shit sprayer.. We have a "bording" section where dogs are brought to stay while there owners are on vacation.. it is my job to walk feed and clean them. I am known as "bording girl" and was told that my only fuction in that facility is to walk dogs. I had asked multipule times if I could be full time and instead they hired two more full time assistants. I and searched for to do the dirty jobs when the other assistants are RIGHT THERE! Basically I am fed up with the place. I want to quit but at the sametime I don't. I am their most valuable employee. I work from 2-4 everyday except wednesdays and then at 7am saturday to 12pm and then again at 4pm until I am done walking dogs.. Sundays again from 7am until I'm done and again at 4pm until I'm done. I work the shittiest hours doing the shittiest jobs that no one in their right mind would want to do. AND I never even asked to work weekends it was just expected from me. Basically I'm stuck in a rut of not being able to move out of my parents house bacause I don't make enough but I don't wanna quit my job. I'm also sick of not being qualified to do anything! I've been working there for A YEAR! I know how to do everything but all of a sudden "I'm not qualified"...? ugh so sick of it. But what am I to do? I guess I'll just have to live with walking dogs and spraying shit down a drain until I find a new job :(