Need advice with New Mustang involved in bad accident

[Venom09]

Long story short some woman rear-ended my BRAND NEW 2004 40th anniversary (3 weeks old 1000miles) while I was stopped at a red light. She was going 50-55. Now I'm sure you can picture the amount of damage that would do to the rear end, however if anyone would like to see pictures feel free to pm me and I'll send them along. I am waiting to hear final word on whether it is worth fixing or not. If it is worth fixing I need some advice on questions to ask. I am concerned about lasting damage that could cost me down the road, especially to the suspension and transmission. Any help would be greatly appreciated.