how to stay positive

Having a  bc diagnosis is a bit like having a toothache (but worse) - your whole head revolves around the discomfort, you can't stop probing the tooth with your tongue, you know what it's like. And you know the only thing that works long term is to go to the dentist!  Which is your next step, as planned, so you are on your way. You sound like the sort of person who can deal with lots of stuff when you are informed, it's the not knowing that is such a worry. Once you know what's happening, what your surgeon is proposing, you can swing all your energy into treatment and getting better. So hard with little ones, but if you can follow the advice everyone here will give you - one step at a time - it really does help. Trying to pre-guess, plan too far ahead just sets up possible problems that may never happen. Stay away from Dr Google, and think how friends and family can help you short term. There are lots of people here (and I am sure elsewhere) who can and will help. You can do it.