Leash in our Mum's group there are I think 7 babies... of those I think 2 still wake at night all the time, and a couple do it on and off. I really believe that some babies just are more wakeful than others. I don't think as mums we are doing things so differently. It's just temperament. Funnily enough the one that wakes up more than 3 times a night always seems to be the happiest most chilled out baby there!
You're doing a great job....