My advice is to stop finding women that are not seeking out dates from men and instead do your searching on an online dating site and look for women that are within a bus ride from you so that you eventually can meet them face to face.
Do you even know where this piano woman lives? Would you ever be able to meet her if in the unlikely chance she wants to? What is the good of an online talking relationship? You don't want to get in the habit of stagnating yourself from meeting women in real life over some fantasy pen pal situation so get out side and mingle.
If you contact this girl, do it just to tell her that you enjoyed her playing and then go out and meet real women with whom you can soon meet and get to know one-on-one.
“The willingness to accept responsibility for one’s own life is the source from which self-respect springs.” ~Joan Didion