I'm so sorry you are facing all this, none of us ever wanted or expected to find ourselves in this position. You are right in thinking that it is difficult to plan anything too far ahead until you know what your path results are and therefore what treatment you will need.
You have probably heard it already but it really is the case for one step at a time, the first step being surgery. Concentrate on having yourself in as good a position as possible for this. I kept up my regular walking and this helped me emotionally as well as physically. I too went searching for as much info as possible. I think it helps to read up on what to expect. Once I knew I was to have a mastectomy, I researched what I would need for hospital and afterwards and went shopping for this.
This site is a great place for info, advice and just to 'talk' with others who have been in the same boat. Once you know what surgery and treatment you will be having you can find a lot of info in your 'My Journey Kit' and advice from the many women who are going through or have been through this. Adean is right when she says that you must put yourself first during this time. Others will understand and everything has a way of working out.
I have had a mastectomy, chemo, radiation and am now on tamoxifen (hormone therapy). I am recovering well and can tell you that you do get through everything and I am enjoying life again. Wishing you all the best. Let us know how you go. Take care. Deanne xxx