Yes, I know what you mean. I always thought I had protection from those diseases while I was menstrating. However, now that I am in menopause, I worry about heart disease constantly. Much of this is due to the anxiety that goes along with meno.
The only thing that you can do is to keep exercising,(walking) check your cholesterol, keep your blood pressure under control, and if you have a family history of heart disease, get checked by a cardiologist. Also, watch your fat intake.
Well you can't die from menopause cause it's natures natural way. It's the way women are designed when reaching mid-life. Now, as far as the estrogen goes, we lose it as we go through perimenopause to hit flat when we are post menopause. So if you are concerned about your heart and estrogen, then you can take estrogen or find natural estrogen products and use them. If you take estrogen and progesterone while you are perimenopause, you can take this up to five years during the course and you will be fine. AFter five years, well they have no further study with this and cancer and heart atacks, so can't help you there. Anyways, this is my opinion and the opinion of my gyne.