Where's Arwen's mother?

[Legolas'Beloved]

It's basically as simple as that. Where is her mother? In the book, it says,

"But her brothers, Elladan and Elrohir, were out upon erantry: for they rode often far afield with the Rangers of the North, forgetting never their mother's torment in the dens of the orcs."

So, is this saying that she was killed by the orcs? And why was she killed by them? Also, another question about elves: If they are immortal, what happens when they get stabbed? Does the damage just heal or do they die and then come back to life? But, it seems like I remember reading something somewhere about them going to a place and wandering around for a little while then coming back to this world. Was I just dreaming or do they go to like a wandering place? And one more thing: Does anyone know if Legolas is immortal or mortal. And to clarify something: When Arwen gives Aragorn her charm, is her immortality in the neckalce or was it basically like a promise ring thing? Ok, so, I think that's all! [img]smilies/evil.gif[/img]