Sorry to hear about your problem. The symptoms which you are describing can be explained due to two conditions. One is known as duct ectasia and it commonly occurs around the time of menopause
and can lead to the formation of abscesses (red, painful lum) close to the nipple associated with discharge. There is also a small possibility of it being cancer.
My advise to you would be to visit your breast surgeon and have your condition evaluated. In addition get a mammogram
and a sonomammogram.