Rehearsal dinner etiquette

I have never been part of a wedding other than my own therefore I’m not very familiar with the etiquette. Is the spouse of the best man invited to the rehearsal dinner? My husband is the best man for his friend/employee. I have met the soon to be wife 3 times. At my gender reveal, our son’s first birthday and the company’s Christmas party. I was under the impression the spouse is invited as a plus one but I wasn’t invited. lol I’m not mad at all or hurt I just found it weird that I was excluded. The groom even asked my husband if I would be attending the wedding which I thought was weird as well. They are both nice people and I have always welcome them in our home.