My dog keeps eating blankets

So I have this small little Jack Russel mix. She's been living with us for about 3 years, but she's about 7 years old now. When we first got her she was terrified of human contact and we suspect that she was abused at her previous home (you still can't touch her tail). She's real lovable and really wouldn't trade her for anything, but there is this weird habit she has. She eats blankets, she doesn't just chew them up, she literally eats them and poops them out. It's not a health issue (I've had her checked). I'm not sure what to do, she has probably destroyed thirty blankets since she came here.