Hi,
As you are already past menopause, the body has probably adjusted to declining hormones. Hence you should not have many changes after the hysterectomy. I think you should be able to cope up well, leaving apart the stress of surgery.
Hope this helps and good luck.
You may need to take hormones because you can have hot flashes and mood swings after the surgery. I would recommend talking to your Dr about this before the surgery. For 6 weeks you should try to rest as much as possible, not take stairs, lift anything heavy or have sex. Even though you will probably be feeling much better by then your still going to be healing inside so stick to the 6 week Drs orders.