Willow, I did a similar thing to PP with DD at 7 months. I stopped feeding her overnight and just sat rocking her back to sleep when she woke at 3am. DP and I took turns at this and it took 3 nights for her to not wake so ours was a bit quicker. It did require both of us to be strong and work through it with her but it was 3 nights of sitting up for over an hour to get her back to sleep until she stopped waking.