Nervous and new

Hi all. Im a 53 year old single mother of 2 adult children with an elderly mother who has been battling lung liver and bone cancer for the last 7 years. She lives an hour away from me with my awesome step father whom also is being treated for prostrate cancer.
I was diagnosed as having grade 2 invasive ductal cancer 2 weeks ago and am having surgery in 2 days. Needless to say its already been a turbulent roller-coaster and I am reeling inside. I have no idea what type of cancer (I read a lot of estrogen positive, triple neg etc type of described diagnosis but haven't been told anything like that as yet) but I believe its been caught early. I have been having regular mammograms for 7 years due to having found a cyst and I had a mammogram in March and was given the all clear. About 3 months later I lost weight and noticed the lump felt a bit different but put it down to my weight loss and bein able to feel more of it. Then about 2 months later my half brother died of cancer. It was throughout his whole body and in his brain. He lasted 4 weeks from diagnosis to death. That prompted me to get another check in late September. I was told on October 1st that the lump was now cancer.
What I wasn't prepared for is how instantly life changed. Some good but a lot bad. Its in my head most of it Im sure but its happening none the less. My friends seem distant. People I would thought would be there are making me feel so alone. Promises of visits then excuses why they cant visit. I live an hours drive from my 'best' friend and used to regularly drive to see her. Now the drive is way to far for her although she drives just the same distance to see other people. Its just hurtful and a hard thing to face and accept along with the breast cancer diagnosis and up coming surgery/treatment. 
However there had been good things happen. I am discovering there are wonderful people in supports online and in person. I quit smoking without one bad craving and I am now even more determined to get through this new phase of my life and come out the other side stronger and healthier. 
I don't know what the future holds but Im aiming for the positive. Ive just got to get through this upcoming surgery first. One thing at a time. I cant think too much about whats next because gets a little to heavy and scary.
Just keep swimming is my new mantra.
My friends will either be there or not. Their choice. I am still me...I think they've forgotten that. Maybe? Time will tell.
I wonder who else has had their long term friendships change.