What you believe to be the best thing may not be. As others have pointed out, she could actually end up losing her child(ren) if she chose to follow your advice - regardless of whether paternity has been established at this point or not. If she loses her child and the state places her in the father's custody, what good did that do?
I agree wholeheartedly that she's in a bad situation. However, you really need to be more careful; you need to consider the long-term outcome when advising someone in such a dire situation.