We went through a disparity of both wealth and income situation, too. It was compounded by an inheritance. We worked out an equitable spending plan to even out the initial income inequality. (Over time that inequality reversed.) Also over time and comingling of assets, it became even more moot.

Originally, we lived rent free together, allowing my SO to bank a huge fraction of income. Over years and over the power of compounding, each of our individually earned IRA and 401K assets dwarfed the original wealth. Now we are FI. I am spending down my inheritance for us to live, and paying the taxes of converting my SO's money to 100% Roths. The short goal is for each of us to have $1M in Roths. BTW, the initial inheritance and saving disperity was $200K. It's $350K now and we've been living from it for years.