Northerngirl, I would strongly advise you to consult a private menopause specialist. Nine times out of ten, if HRT is problematic or simply doesn't work, it's because you are taking the wrong type and/or the wrong dose.
The NHS can only deal with bog standard HRT at bog standard doses which are very conservative. They can't give specialist advice and because they don't routinely offer uterine scans, they over prescribe the progesterone component of HRT and that is why so many women have side effects they can't live with and give up on HRT altogether.
I would look for a menopause specialist with a particular interest in osteoporosis/osteoarthritis. Definitely sound them out before booking an appointment too.
I hope that helps.