Liability for car accident; just cancelled my insurance as selling car; who pays?

Next time, don't cancel your car insurance until the car is actually sold.  By driving without insurance, you leave yourself open to a motor vehicle violation for that, which usually brings a license suspension and a fine, if you're pulled over or if the police investigate an accident you're involved in, even if you aren't at fault.  And if your mistake causes someone to be seriously injured or killed, you could lose everything.

When you talk or write about this, you need to work from as definite a recollection as you can honestly put together, after you take some time to remember the accident in detail.  Having a "suspicion" that the other driver had her lights off or made an illegal turn isn't going to do much to assign fault to her.  You can assume, until you hear otherwise, that she will be quite certain she was driving properly, with her lights on.