Hello to all....... I'm chiming in here and first want to say that what I'm about to say makes me sound like a 'negative nabob' but that's really not my intention.
The AI's were not an option for me. I tried 3 of 4 available over the 5 year course of my Stage 0 to Stage 1 (bi lateral mastectomy) journey. I tired Tamoxifen -raised my blood pressure to extremely high levels, Letrozole - got Shingles and joint pain and severe depression (I'm never depressed, I can't be, I'm far too anxious, ha ha), Arimidex - blood in my stools and a rash for over a year along with severe depression and joint pain.. I'm not taking the meds now at all and my doctors are recommending that I take them only if my cancer comes back and of course, I'm hoping it won't!!!
From my personal experience and what I've read on this site and many other places - AI's have side effects and most people will experience at least some of the side effects. Many people experience, as I did, extreme side effects. Yes, some of what you feel might be simply the reduction of hormones in our bodies and something you might experience with aging (but much more slowly). This is taking all of your hormones from your body in a very, very short period of time, causing the many side effects. But, there is something else here with AI's........they are doing something else, in addition to reducing the hormones and I believe that's what really causes the serious side effects. I don't know what that is but what you are feeling from these drugs is real......it is not 'just you', it is not that all women are simply taking these pills and you are the one who can't tolerate them. It's many, many women out there. So, hopefully, if as they say, misery loves company, we're not alone.
I was lucky and I am grateful that my cancer was only Stage 1, it had not spread and that made my decision not to use AI's a little easier for both me and my doctors. But, what I did ask for was on going blood tests to determine the estrogen levels in my body (I had lots of estrogen, no progesterone) fueling my cancer. For over 3 years now my blood levels are below normal for estrogen. My body still makes it they say but in such small amounts it's not recordable. And due to the low estrogen levels I now have (and no progesterone or testosterone - which can convert to estrogen) I do have changes - hair loss, some joint pain, wrinkles, saggy skin....you ladies all know the aging complaints if you're of a 'certain age'. But, I do not have depression or a rash or severe joint pain, etc.....those all stopped with the run through the AI's.
Am I afraid of cancer recurrence? Yes, everyday. It's the new 'not so normal'.
I did change my diet, lose weight and change my lifestyle to include more supplements, Vitamin D, Omegas - more exercise, etc. My health is better overall than when I was diagnosed with cancer and I'm lucky again - I have no other health conditions......

My message I guess is to know you are not alone - side effects from AI's are very common and what you feel from them is real. It's hard to gauge their overall effect on your physical and emotional health in some ways because after you are diagnosed with cancer, endure treatments and deal with all of that you are tired and emotionaly drained. It's hard to add yet another onslaught of symptoms and feelings to navigate.

Ask your doctor for blood tests to determine your hormone levels 'off' the drugs........what is your baseline? This may take a couple of blood tests spaced over several months, but you should at least know where you are starting. Once I requested that and my doctors saw that I had so little estrogen to feed my cancer, they were less inclined to recommend the AI's. As you continue to use the AI's, request blood tests to determine how much effect they are having on your hormones so you can weigh that against the side effects.

The AI's work, they help you fight cancer and cancer recurrence. It's up to each of us to determine what that cost will be and how much we can endure......and that's the hard part because it's on us as patients and weighing feeling miserable for 5 years against getting cancer? Not much of a choice and a very difficult one to make.

Hugs to all.