Dark days

Just diagnosed this month, 1.5.cm invasive tumour, plus 3mm by 3mm tumour I couldn't feel. I am 46, have had regular mammograms and ultrasounds for years due to lumpy, dense breasts. I self checked religiously and I still didn't feel this lump until it got to 1.5cm. I had lumpectomy and sentinel nodes out one week ago, and now find 5 out of 6 nodes have malignant cells, and the margin around the larger tumour shows carcinoma insitu that needs to be removed, so I am having a full mastectomy Monday plus full axilla node removal, portacath inserted and I will start chemo before Christmas. I have 4 children, youngest 7, oldest 16 and telling them was horrendous and watching their fears and answering their questions. Trying hard to keep going as normal and reassure them I will do all I can to be here for them. I have a CT of chest and abdomen today that surgeon tells me is just a baseline for the oncologist for chemo but I am terrified it will show metastisis somewhere in there and it will be too late. Its been one month since I found this lump and made an appointment that day with my GP and I feel like this diagnosis/surgery/treatment thing is taking forever. I just wanted it out the day I found it.
 My husband is amazing and this is bringing us very close as we realise we can't take each other for granted any more. I have a very supportive family and have so much to be thankful for when others struggle through alone. But, feeling very alone and scared right now. Thanks for reading.