We are in the same boat, my wife is life long Bama girl. We just decorate the house with LSU and Bama gear for the rival games and love it. The 2010 game she got pissed at me but other than that its been mostly civil Btw our kids are split too. My youngest is bama, and the two older are LSU. Geaux Tigers!
What an interesting problem. My guess is the more famous the venue-the more fans from both sides will be in attendance. The main bar at Pat O'Briens, say would have both-probably. The Rusty Nail has lots of ambiance but you'd be left out. Hotel bars don't have much soul but you'd be kinda safe in finding fans from both sides. I am a big fan of Ditcharo's. For big games they put a huge screen outside and have a block party. If I hear anything I'll let you know.