I also wonder why you haven't tried HRT. You said you've "managed without it", yet your first post clearly seems to indicate that you really aren't coping all that well because you said you're "still struggling".
With HRT there is nothing to fear, but fear itself. So many women have been fooled into thinking it's dangerous, or causes cancer, or whatever, yet none of those things are actually true. HRT has just been a victim of a very vindictive smear campaign by the media. So bad was the campaign that even some completely clueless doctors believe it.
No one can tell you how long your symptoms will last. It's definitely not guaranteed that you will get through it within a couple of years, or even 5 years as some will tell you. You could be lucky and an improvement will be just around the corner, or you could be like a lot of women who are still experiencing symptoms into their 70s.