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.
I truly aim to please you as a customer, but please keep in mind that I do not know what you already know or don't know, or with what you need help, unless you tell me. Please consider that I am answering the question or question that is posed in your posting based upon my reading of your post and sometimes misunderstandings can occur. If I did not answer the question you thought you were asking, please respond with the specific question you wanted answered.
Kindly remember the ONLY WAY experts receive any credit at all for spending time with customers is if you click on OK, GOOD or EXCELLENT SERVICE even though you have made a deposit or are a subscription customer. YOU MUST COMPLETE THE RATING FOR THE EXPERT TO RECEIVE ANY CREDIT, if not the site keeps your money on deposit.
Also remember, sometimes the law does not support what we want it to support, but that is not the fault of the person answering the question, so please be courteous.