Here's one explanation that Google found:
Would you please tell me the meaning of this word?
Thanks in advance,
"Bridezilla" is a word that has been coined in recent years to describe a woman who is about to be married that is going too over the top with her preparations and demands. A Bridezilla spends money she doesn't have on an elaborate wedding dress and ceremony, she's very stern with her attendants, ordering them around like she's their school teacher or mother, and she makes unreasonable demands on her friends and family.
There is an interesting linguistic event happening here. When I was a little boy (the 1950s), there was a movie called Godzilla. It was probably the first Japanese monster movie to be popular in the US. Since then, -zilla has become an English morpheme (unit of meaning, but not a word) that means "monster."