Larryace....I agree 100% with your frustration.... its really unfortunate the band will ultimately suffer. I have experienced a huge amount of DRAMA from the females that attend our shows, and shows of the past. It has even caused me to leave good money making gigs on the table, because the band's entourage has too much drama.
My humble opinion is to flat out tell the singer his wife is 'banned' from attending shows.
He may be super pissed, and threaten to leave the band, but guess what........its either that or it will be the demise of the group and probably dissolve it long term. Two bands in baltimore (that were on the bar circuit) I know personally have had the exact same thing happen, and they are no longer together.
Here just my observation, maybe it will help.
1. Drunk women, especially drunk, jealous women are impossible to reason with. If they complain to the bar owners, bouncers, head bartenders, about any other patron, because of their own insecurities.........they just won't book your band anymore. You will get labeled as the band "will all the drama"
2. If anyone's band wife/gf interfers with the safe, harmless good time of other paying bar patrons.....the band doesn't get another chance. Blacklisted for good.
3. If your frontman can't interact well with the crowd, the bartenders will get mad and catch shit from the paying drinkers.If your singer has to be "on their best behavior" because their significant other is in the room, it will come across as phony. Not to mention, bar patrons will say the band is arrogant and playing the rock star role. Lose/Lose situation for the band, again.
4. Let say you have jealous wives/gfs at the show. People absolutely pick up on their negative vibe. Even if they love your music, they will learn not to attend the shows because of the drama. Then the gig (and the money) go to another act.
5. I have learned personally, there is nothing more damaging to a band, its reputation, its paycheck, then women would are insecure troublemakers. Tell them to get over it...drunk women will be aggressive, playful and flirty. Band members have to be slightly flirty and friendly to everyone.....thats just the bar business....too bad not all the women attached to the band "get it" or understand the music business.
So, thanks for letting me vent. I could go on and over this one topic because its struck a nerve. I just want to contribute my 2 cents, because Ive experienced exactly the same thing. In fact, one ex singer/frontman i had the pleasure of working with actually got into a huge fistfight because of his wife. bad scene. Hope your plays out well and something positive comes of it.