My DD was a snacker too, from day 1 she wld only feed for about 3 minutes max! Thats probably why I have never had more then 3 hrs sleep at night! Nowadays she is just a full on boobie monster and wld be happy to be attached to me all day, just like she is all night! :/

Im pretty sure all babies go thru the pulling off when they start getting curious about whats around them, a necklace wld probably help though. You can get necklaces that are bright etc especially for breastfeeding. I think I have even seem them on Pinky McKays website. Like the others have said try and ride it out and hopefully it passes quickly! Maybe u cld try detaching her urself once ur letdown finishes so she doesnt hurt you when she does it?? And then just try and feed her hrly during the day with short feeds to try and cutback on some of the night feeds?? Good luck!!