The journey to FEEL like my money is John's, and John's money is mine, is a long, slow one. My family of origin handed down some real gems when it comes to beliefs about money, the value of work inside and outside the home, gender and what is worth spending disposable income on.
That said, John is much farther along in the "it's all ours" belief than I am... but much farther along should make you laugh when he told me where his 401(k) is at. I was delighted that he has saved and matched such a wonderful start to retirement, and said, "Well, mine's not quite as much." (Given that I've had benefits for about 8 months and he has had them for over four years.)
He responded, "Oh baby, all that money is ours."
Me: "Aww, that's sweet."
Him: "Well mentally it is. But also legally!"