So sorry to hear that, @tisme. I've been on Anastrozole for just over 4 years now & still going OK on it (MUCH better than when I was on Letrozole and Exemestane!)
That's great that your Onc lowered the dosage - how long ago was that? Has it made a difference? When do you see them next? ...... Have you had a complete break from it yet, for a good month or so? To see if it can 're-set' so you hopefully get not as bad side effects?
Can you talk to your breast care nurse about it as well?
An online group that I am in (lots of overseas people on AIs) has had some success with taking Tart Cherry Juice - Studies show that tart cherries can help reduce the pain and stiffness associated with arthritis and other joint pain disorders. Several studies have shown tart cherry juice to aid significantly in exercise recovery and muscle pain after exercise. Others have gone on short doses of Steroid Tablets to reduce the pain ... but it can't be taken long term.
take care & good luck xx