What is the statute of limitations for personal injury (hit by drunk driver) in Colorado?

Just over a year ago, I was in an accident. The driver of the other vehicle was passed out veered into my lane. I did all I could to prevent a head on collision, however the collision was inevitable. He destroyed my truck, trailer, & load. As well as the car he was driving. I was transported to a local hospital, for low back pain evaluated & sent on my way, as there was no major injuries. Have still not received much treatment for what was originally diagnosed as a sprained or strained sacarelium, & later also as a bulging disc in my neck that has flattened the spinal cord at C 5-6 couldn't get any of the Drs approved by my, occupational insurance to see me, have been seeing my family dr. Since the accident, he tried to send me for PT & PM, & my ins denied the treatment. Was going to a chiropractor for 7 months until the pip on my employers ins & my ins was exhausted. Now my ins has cut off all benefits, because their IME concluded that because the neck & shoulder injury did not present until 2 weeks later, & I have slight degeneration of the spine. That it can't be related to the accident, & it had to be a illness not a injury so after a 5 min. appt. In September he declared me healed to a pre accident state as of July 31 12. & in Feb / 13 said I was ready to return to work, he has not seen me since September/2012. Now I have no income, because I can't return to work, & I have no coverage to be able to get treatment if & when I find a Dr that will treat me. I do have MRIs of the neck & upper back, but haven't been able to get anyone to do anything about the low back, even though it continues to hurt, & is getting worse as we go, so not even any proof there is a injury. What can I do now, & when do I have to file on the driver & his insurance for personal injury, the accident was 3/10/12. I am from Texas but the accident was in Colorado. The drunk driver was care flitted to Denver with a compound fracture to a leg.