I didn't take HRT. When (mid-fifties) I got fed up with my periods getting very irregular (sometimes 2 - 3 weeks between them, sometimes six, and always pretty heavy) and with being rather more emotional than usual, I asked my GP for HRT. He said "Come back when it is complete and we'll talk about it then" so I went home and just got on with it, though I did relect that I thought the HRT was to help you get through the change, not to start on after it.. The periods soon stopped altogether and I didn't get the awful symptoms I had heard about. I had some flushes, but not the sweats or the mood swings. I am glad now that I didn't take it. I have been 30 years without added hormones, and I don't miss them. I am as healthy now as I was then, apart from getting puffed-out sooner when going uphill. My joints are not painful, my hair hasn't thinned, and my brain still works.
If your periods are dwindling away, I would say your production of female hormones has slowed down considerbly and you are coming toward the end of the actual change-over process. If you are not getting the more unpleasant physical and emotional experiences by now, you stand a pretty good chance of missing out on them. Follow you instincts - retune your diet to get the vitamins etc that your body needs, keep up all the things that keep you fit and happy already, and find out what problems you might come across without the oestrogen and other hormones so that you can counteract not producing as much of them, if necessary.