<human>: Hey Reddit, I just got hit with a $1K bill from a car insurance company and I'm not quite sure what to do. 

About a year ago, March 20th, I was Longboarding and ended up hitting my friend's car as he was rolling up to a stop sign. 
1) Longboards are restricted to sidewalks in this state 
2) I crossed over into his lane due to gravel being in the road, which prevented me from turning sharp enough.
I know that based off of that, the fault is completely mine, BUT, my friend told me that he was texting when he was pulling up to the stop sign and didn't even notice me until I had hit his car. I told my friend that I would help him pay for the damages, and I kept that fact that he was texting on the down-low for the police report and when his insurance called to gather information. 

For the next 2 months, I continued to ask him how much he was going to need me to pay, and he kept saying he would get back to me. I haven't heard from him since he graduated last May, so I figured he ended up not needed me to help pay for it. 
Today, I checked my campus mailbox and found a letter from his insurance company, "seeking reimbursement from you for this claim and for out insured's deductible." It was dated March 2nd and it stated that I have 28 days to send them payment before they "forward this claim to an outside vendor for further handling."

This totally blind sided me and I have no idea what to do, so I figured I'd come here for some advice. I'm just a 22 year old college student =/

Can you provide a brief overview of the text?
<bot>: Hit my friend's car while longboarding a year ago. Never heard from him about payment. Got billed for all of the damages from his insurance company today.