Disgusting character of Ms. Annabeth Gish

I know it's not her fault, but I think that a good actress can ask the writers to put more interest when are developing a character like this of Greta Siegel.
The woman, a bit mature woman, is acting stupidly all the time, and we can guess why, but she is not capable to give a simple explanation of her stupid behaviour to the poor and confused Dave, more than that. she barely talk in the whole movie.
I know is a comedy but it's not of the slapstick kind. It's of the kind that people acts in a weird way... but talk about it.
Bad work of the writers and very bad of Ms. Gish, all is wrong with her, very inexpressive, horrible make-up, she appears all the time as coming from the shower.
All wrong and I rented the movie to see her.