Old Mutual Annuinity policy

i am totally disgusted and sadden with the outcome from Old Mutual with regards to me wanting a certain amount of money from my Annunity policy.The reason for me requesting the amount is due to me being unemployed;diagonised with Parkinson's;and me requiring the funds to buy my chronic medication on a monthly basis. i have invested this money over a period of over 10yrs and now I am in this financial situation they are not prepared to help me out of this stressfull cash situation. They are saying that the policy which i have agreed upon is a Annuity and can be changed on anniversary. and stating in terms of government legislation and effecting the shareholders.