Sorry to hear this @"jackie 4" . I still get random problems after 12 months but manageable. My worry is bone density as am already osteoporotic.
A couple of random thoughts that may help. I have been told on here the pill coating of the generic Letrozole can cause problems for some that the branded product Femara with a different coating may not. Have also been told on here that sometimes switching type of Aromatase Inhibitors is sufficient to make side effects more tolerable.
Either way 2 years is a pretty good test and maybe time to talk to your oncologist about it.