Hi! I have the same problem as you. I had mastectomy in 2014. No radiation or chemo, took tamoxifen about 3 years. It caused too many side affects at work. I started having problems 3 years ago. The doctor checked for heart problems, no checking for cancer even when I told him it didn’t feel like a heart problem. He knew I had breast cancer but never checked for that. Symptoms kept getting worse, went to a different doctor 4 months later & she ran a whole bunch of tests and found Mets to lungs , ribs, spine, hips. I was on Ibrance & Letrozole for over a year & a half until it quit working. They tested me & found out the cancer had a Pik3CA mutation. I am now in a stage 1 clinical trial of a drug that targets it. I have been on it about a month, no side effects yet. Hopefully it works. Only my close family members know about my diagnosis no one to really discuss things with. I don’t want my family to worry about it. Doing ok otherwise.