How much will it cost to fix my car when i rear ended someone?

so i was driving on the highway the speed limit was 60 i was going 50 maybe 45 and there was construction on the on-ramp so everyone slammed on their brakes. even the guy i hit said there was nothing i could do. but the whole front end is busted his trailer hitch was about a foot long and went right through my radiator and bent all the metal back towards the engine there was also some sort of fluid leaking i have no idea what it was. i just wanted to know if any one would know how much it would be to fix. my insurance will pay but i wanna know if it is totalled and i should start looking for a new car or would they fix it. to tell you the truth i want it to be totalled. the car is a silver 2003 oldsmobile alero.