Could you have some simple, busy work task for her to do that would keep her busy, but make her feel important? I don't know....like maybe folding napkins? Or if you are using plastic plates--counting plates and silverware?

Heck, could she stuff envelopes (assuming that your organization mails anything out)? Or stick return address labels on envelopes? Do you make goodie bags to hand out at Halloween? Have her help stuff those...
I don't know what she's capable of doing, and doing in a safe and sanitary manner.

I know it's frustrating, but I think that she's really needing the attention (and you seem to know that as well), it's just that her "neediness" is just at a particularly bad time.
My 8 y/o LOVES to "help" me in the kitchen--to the point that he was always in the way. I finally figured out that if I let him do something helpful, and then took the time to cook with him--it was a lot less headache on both of us.

__________________
Mental that one, I'm telling you. ---Ron Weasley, "Harry Potter and the Chamber of Secrets"