You're not being negative @simo. Hearing those words that you have breast cancer is bloody terrifying. The time from diagnosis to surgery was for me one ranging from utter despair to numbness and back again. I had lost my older sister to this 20 years before (she got it quite young). I was so worried to not be there for my kids who were 11, 12 & 15 at the time. Two years on (on Thursday just gone) and I'm NED (no evidence of disease) - that's the best it will ever be but that's enough.
As @arpie has said, minimising treatment is now recommended as there is no difference in the outcome. However, that does not mean that the treatment is less, only that it will not be more than is required by the presentation of the cancer. Mine should have been a lumpectomy followed by radiation, but due to the type of cancer it was (lobular), when the surgeon went in, it was impossible to get clear margins and it had spread to the nodes even though it hadn't been detected on the scans. Back I went 2 weeks later for a mastectomy and axillary dissection, followed by chemotherapy and then radiation. So, just because the less impactful treatment is recommended, does not mean that you won't get what you need if it should turn out that way.
I don't know how old your kids are but my advice would be to tell them what is going on as is appropriate for their ages and, if they are old enough to understand it, that you will always tell them what you know and not keep secrets. Secrets can be very scary things to kids and they need to know that, no matter what other thoughtless or well-meaning people say to them, they have the inside knowledge.
Do you have a partner or friend here that you trust as an advocate? If you can, take someone with you to appointments. It's amazing how much information doesn't get through the fog so it's good to have another pair of ears and someone who can ask intelligent questions. Most doctors expect it and even suggest it. If you haven't got anyone, ask if you can record your appointment so that you can refer to it. And if you have questions, write them down before you go in.
If your anxiety is becoming overwhelming, please try to access counselling with someone who understands cancer. As with everything, there may be someone on the forum who can provide some assistance with local information - add your general location to your profile but never be too specific.
My only other advice is to try to take one step at a time and one breath at a time. You will get through this and we are here to support you.