failing to pay my vehicle's damages

My car was involved in a car accident on the 10th of march 2015, where outsurance client bumped my vehicle and he was wrong. I have put my claim with them as a third-party as per claim number ***. I have send all the documents needed and picture of my vehicle and have also send me to the assessor who said my car is a written off. I have then received an e-mail from them which is stating that I am also wrong and will end up paying them a certain amount of money. They are using their jargon not to pay me while their client tried to kill me. I want this matter to be resolved in a right manner.