Who is Brida from By the River Piedra I Sat Down and Wept and what is their importance?

Brida is a woman that Pilar meets in Madrid. She attended the meeting that Pilar's friend held. Once Brida sees that Pilar knows the man that gave the lecture Brida heard, she immediately goes to her. At first Pilar thinks Brida is odd. She openly prays to a statue, ignoring the people around her that point and laugh. She is very spiritual and understands and accepts the idea of the feminine side of God. She is a devout Virgin follower.