Good morning! So sorry to hear you've been through all of this. Hormones.....for some of us they are a tricky mess. I was diagnosed 5 years ago with atypical ductal and atypical lobular hyperplasia. It was the lobular that got me in the end. I had lumpectomy and like you was being monitored for invasive cancer for two years. They found invasive cancer 3 years ago and I opted for a bilateral mastectomy (although a lumpectomy was a possibility). In my case, the ADH and ALH was in my left breast and the invasive ended up in my right (very typical of lobular cancers....both breasts)....hence the mastectomy. And I too had large uterine fibroids and a history of ovarian cysts. I was fortunate in that I was going through menopause at the time and the fibroids and cysts resolved themselves (but not without considerable discomfort and worry)......It's those pesky hormones. The management and leveling of hormones (in my opinion) is very much overlooked for women, resulting often in the serious problems you've experienced and that many of us are dealing with now.
Keep up with the MRI's and Ultrasounds......they saved my life. I was diagnosed at Stage 1 with no spread to my lymph nodes and I was very grateful for the on going monitoring because I caught my breast cancer early. I was unable to use any of the AI drugs.....like you, serious side effects but I have made as many positive changes as possible to improve my health and hopefully calm those hormones (diet, losing weight, no alcohol, quitting smoking, supplements - Vitamin D, Omegas, Tumeric, etc).
Sometimes it doesn't come back..........I am hoping that for you, but do be diligent in getting your tests so you can catch it early.
You've been through a lot already and you're young. I am so sorry. Stay healthy, stay positive and perhaps ask that your doctors check your hormone levels (they are numerous methods)...so you can monitor that as well. It can help you make the decision (as needed) on the AI's
Hugs and wishes for good health to you!