Legal Question in Civil Litigation in Maryland

Since your friend sued you it's up to her to prove her case. You didn't supply any facts, so it's impossible to provide a specific response. If you never received anything from her, you will obviously say so in court. If your suit is not in small claims court, you can send her written questions known as interrogatories before the trial asking her to provide whatever proof she has to support her claims. If you did receive something from her but you think it was a gift rather than a loan, that would be a defense to having to repay her. The court will have to decide that her evidence outweighs yours in order to require you to pay her back.