If your mother is the only family member who has had breast cancer, then it is likely not genetic. That being said, the BRCA gene is not the only one they can test for. I had genetic counseling and testing because there's a lot of cancer (including breast cancer) in my family. I was negative for BRCA. However, five years after my genetic counseling, I got the breast cancer diagnosis. So go figure.
I will just say this regarding hormones... I have oodles of cited studies given to me by my gynecologist that shows hormones do not cause breast cancer. If you have a hormone-positive breast cancer, then hormones can feed it. So it would be helpful if you knew what kind of breast cancer your mom had - generally the classifications are either estrogen positive/negative and/or progesterone positive/negative, and HER2 negative or positive.
This all being said, there is also much being reported on the benefits of prescribing estrogen and progesterone past menopause. Personally, I went into surgical menopause when I was 54 when I had to have a complete hysterectomy due to endometrial cancer (caught very early so only required surgery... no chemo or radiation). So the day of surgery I was still producing those hormones (although I was in perimenopause), and by the evening I wasn't producing anything to write home about. About three days later I started having horrible hot flashes. It really impacted my sleep, so at my six-week follow-up with my gynecologist, we decided to start some hormones. We started very, very small, using a gel that I applied to my forearm. We increased it over a few months, but it really didn't touch the hot flashes. So eventually about six months post-surgery, he put me on the patch and my life turned around. Over the years I've been able to decrease the dosage to a pretty low amount right now. I still get hot flashes but for the most part, they're manageable and don't interfere with my sleep. The key to my knowing I was having some mild hot flashes was the under boob sweat I'd wake up with in the morning. And then I would occasionally have some very mild 'warm' moments throughout the day. But mine only lasted a few minutes. You might also want to get your thyroid checked.
I would do some research into the benefits of bio-identical estrogen replacement. It's not just about hot flashes. It helps with bone density as we age (but you also need to get enough of the right kind of calcium and vitamin D and lift weights of some kind) to minimize osteoporosis. Estrogen also protects the artery walls and keeps the blood vessels more flexible (also helps with bad cholesterol, although there are always statins you can take); so if heart disease runs in your family, estrogen can help reduce your risks. Look into what a lack of estrogen does to cognitive abilities, skin issues including vaginal dryness (again, you can use a topical for that).
Personally, I have a really high risk of heart disease in my immediate family, so I feel taking a tiny bit of estrogen is something I can do to minimize my risk. My mom had a hysterectomy in her early 40s and had heart disease by the time she was in her mid 50s, having a silent heart attack. She had been a smoker, so that obviously didn't help, but being without estrogen couldn't have helped. One brother had his first stent put in in his late 50s and a second one in his late 70s. Another brother died after his second heart attack in his early 70s.
Also, I do have borderline osteopenia, despite lifting weights since I was 50. I can only imagine what it would be like if I hadn't been taking estrogen since my hysterectomy.
I'm not trying to scare you, but do the research - feel free to PM me if you want to see the bibliography of the studies I have.