I wouldn't worry too much. I do not agree with crying it out, but I know that it works for some people and you have to see what works for you. Just consider, maybe she isn't waking because she isn't able to soothe herself, but just because that is what her body is doing. Don't you have insomnia nights? The difference is that we stay and bed and put up with it, they can't do that. I have personally found that when my son doesn't go to sleep, or wakes up in the middle of the night, it is for a reason. I would suggest that you just keep patient and make sure this isn't just a phase. She is only 5 months old and there will be many hard nights ahead! As she gets older, they will be fewer and fewer. I have never left my son to cry and he is an amazing sleeper! He started to put himself to bed after a little rocking at one year old and he sleeps from 7:30-7 consistantly. Up until then, I always rocked him to sleep. If he isn't going to bed, it is because he isn't ready and there is nothing I can do to change that. I would be very careful about assuming that there is no reason for her to be up. If it was just a matter of her not being able to soothe herself, she would fall asleep during nursing, bottle or rocking. If she is up for hours, it is because her body just isn't going to let her (or you) sleep. It should just be a phase, just try to be patient. With my son, he would wake sometimes for his 4am bottle and not go back to sleep. I had the house dark, quiet and rocked him for hours. If he wasn't able to go back to sleep, I just made my coffee super early! Then, a week later, he would go back to normal. At 5 months old, she is not manipulating you, I swear!