As a professional catsitter, I can honestly say that your cat will be fine! As long as you are happy with the person you have got coming in and they know everything about your wee puss cat she will be fine. She will miss you but as soon as she knows that there is a loving person or as i call myself their holiday slave! They will just be relaxed and happy to be in their own home and getting fed and fussed when the sitter comes in.
In my experience it is the owners that worry more than the cat! I worry when i go away and leave my cats in the care of auntie jane but they are quite happy knowing they will get fed, fussed and pampered!!!
Have a great holiday! Your cat will be fine, I can assure you of that