want to quit job!

i am a teacher in a private school and honestly saying, i want to quit my job because it doesnt make me happy anymore. our employer is demanding and i simply cannot keep up with her pace.. i developed heart palpitation then due to stress.. with this, i submitted my resignation letter together wth my health record but she refused signing it for it was in the mid of the school year..i really want to quit my job cause its detrimental to my health.. the problem is, my contract is for three years. it will have to end on 2014. im planning to do AWOL but im scared of the odds. what could be the best thing for me to do? what could be the worst thing that would happen to me if id go on with my plan to do AWOL..or could i just really resign from my job even if the contract is until 2014?? if i could, what if my employer would not agree??
badly need ur help.. this is causing sleepless nights already. thanks a lot!

i am not aware if there are special rules for for elementary and high school, unlike the manual for private schools for universities and colleges. it may be best to inquire at decs.

thank u..