Is this a new behavior?
Chewed fiberglass? How strange, this might be a sign of what is called Pica, and can possibly be caused by some lack in the body. As a small child one of my daughters used to carefully remove some of my plants from their pots and eat the roots!!! Her German doctor said it was Pica and to give her a vast array of foods to see if one of them calmed and changed her diet. (it did, and she gained a lot of weight too.)
I buy my two rescue cats sprouted greens from the grocery store, I think it's mainly for someone who wants to juice it but my cats graze on it like cattle in the fields.
As for the scratching and biting, treat her like a kid and tell her sharply "NO" and use a spray bottle to reinforce that order. Cats and dogs hate spray bottles with just plain water in them.