Sorry you feel low. It is the loss of oestrogen.
Did your sister have breast cancer or a different cancer?
You might like to do some serious reading up about the actual risks. The medical advice is that it is a warning light if 2 first degree relatives had breast cancer under the age of 45- mother, sister, aunt.
There is also lots still unknown about the link between HRT and breast cancer. Some of the best experts believe that it does not cause cancer, but maybe the cancer was already there and was discovered by coincidence when taking HRT, or that it promoted tiny cancers already there.
I linked in another thread from a cancer charity which showed that women who take HRT as just oestrogen have a lower rate of breast cancer than women not taking HRT, and oestrogen alone with for example the Mirena coil as the progestin part of it, could be the answer for anyone worried about cancer risks.
Are you exercising? Again, some research shows that 30-45 mins brisk exercise a day has the same benefits as HRT.
It depends on how much work you want to put into YOU! Your lines can be got rid of with some cosmetic fillers, you can get a new job, maybe voluntary or self employed if that feels less daunting.
You are still a young woman at 55!
Have you thought about maybe seeing a life coach who specialises in women your age who can help kick start the process and help build your confidence a bit?