Thanks for the replies.  
Just beating myself up today with my inner critical voice...like why can't I do without the surgery, what will people think of me for taking time off for a non critical operation, will i loose my job, home, blah, blah.  What my therapist would catastrophy thinking.  When really I need to, for once, put myself first and not feel guilty about it.
I just know I need the hrt as without it, just on the AD's, I am very flat and energyless.  So by having this treatment, it will enable me to continue with HRT and relatively light periods....that's the plan anyway.