i also breastfeed and cosleep. my son is 3 1/2 months old and has been sleeping about 6 hours a night since about 6 weeks. but he usually wakes to nurse at 2am and again at 4am. since we cosleep, i do the same as you, just roll over and feed him while i'm half a sleep, so it's no big deal. if your daughter is eating noticably less during the day, this could explain the night time feedings she has now developed. she may be just plain hungry. also, if she is teething, this could also explain it. she may wake up hurting and nursing is the best thing to comfort her and get her back to sleep. even though i've read you "shouldn't" i usually nurse my son to sleep. so i don't know how much good advice i've given you, but at least you know you're not alone.