Thank you for your question. I look forward to working with you to provide you the information you are seeking.
As this case can have criminal implications, please do not make any further statements to any law enforcement officers without an attorney, as you have a right to counsel and you need them to make sure you do not say the wrong things here.
First, regardless of whether or not you ever changed over the registration, if you have a signed title
from the owner, then you ARE legally the owner and you can change over the ownership
by submitting the signed copy of the title with a bill of sale or affidavit of donation/gift from the owner and you can get the title switched to your name.
Second, even if you do not apply for the new title in your name, if you have that signed title from the owner and proof she gave you the vehicle, you can give that to the new owner (person you sold it to) and they can use that to get the new title in their name. Thus, you did not do anything actually illegal. You do need to help the new owner get title in their name and you should do so by going to BMV and bring the signed title and proof she gave you the car and go with the new owner and his bill of sale and BMV will change everything over for you to the proper title.
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