My wife talks about divorce and walking out over small fights. Should I just concede defeat?

I think you and your wife seriously need to sit down and have a good heart2heart talk. Divorce isn't something to be taken off lightly, unlike BGR where they are no direct commitments. You're commited with her about your house, kids, car and even families. She may be unaware that bringing up divorce each time during a quarrel is a huge slap to the relationship, so it's best to quickly iron things out. Remember why you married each other and never ever go to sleep mad at one another.