Your mother would do well following the Cycle Diet, essential fatty acids, vitamin and minerals and especially freshly milled flaxseed. I've had a few physicians comment on how heart healthy it really is and that they are also recommending it for their female cardiac patients, post menopause.
Menopause is very different from PMS due to the drop in both estrogen and progesterone. Tell her to stay away from refined sugar and flour if she can and stick with as many whole foods as possible.
Hot flashes can be brought on by excess sugar, alcohol, stress or spicy foods. The fresh flaxseed have lignans that are phytoestrogens. They have the ability to occupy the estrogen receptors without strong cell signaling. Soy isoflavones do the same thing. Some women do well with soy foods like tofu, tempeh, edamame, and soy milk but if she has a thyroid problem I wouldn't over do the soy.
I don't know much about Estretest, I've actually never heard of it. Many women who are having quality of life issues are still being helped by hormone replacement, she needs to discuss the kind of risks and symptoms she has due to family history and may consider something else if she's really having a hard time.
Karey, one of the things I can tell you is if you continue to stay with the lifestyle changes you've made, you will have an easier time with your menopause. It's all about giving your body what it needs. There are quite a few perimenopausal women on the Cycle Diet having good results as well. Oh and congratulations on your success with sticking to it with the holidays!