Is there a reason your spouse isn't working (taking care of children, disabled, can't find work that's meaningful, etc.)?
As a sole breadwinner myself, I think this is a very important question. Assuming the spouse/partner is able, I believe it is very important for both to be contributing to the household's financial future in some way. That does not necessarily mean working for income, because working as a stay-at-home spouse, full-time student, or another non-money-making endeavor can make a very important contribution to the household's future. It was eye-opening for my wife and I to calculate the amount of life insurance I need on my stay at home wife just to account for the value of the childcare services I would need to purchase if she were to pass away.
My wife and I have traded off supporting each other at different times in our relationship. She supported me through law school. Now I support her while she is a stay at home mom for our young daughter. Soon she will be going back to work part time. We are both comfortable with these various arrangements because each of us is/was contributing to our household's financial future-- one brings in income, the other primarily helps keep living expenses down, improves the quality of our home life, and/or invests in the future. There is no way we could be as frugal as we currently are without my wife's non-income-producing contributions to our household. And even though she is primarily a stay at home wife, she still contributes to our income through freelance music gigs and other occasional side-hustles.
There were some times, however, when one or the other of us was merely idle and we perhaps could have been doing something more productive. These were some of the hardest times in our relationship and the times when resentment crept in. And for us, these were just temporary times between bigger things-- a few weeks or months-- and not the long-term status quo. I believe the resentment would have been bigger if it were a long-term arrangement.
You do not want to find yourself in the position of resenting your spouse's/partner's lack of productivity. You need to protect yourself and your relationship by setting the expectation that your spouse/partner will contribute to the household's financial future in some way. Do not unwittingly put yourself in the position of financing someone else's financially
dependent early retirement while you squander your own retirement-- early or otherwise.
This is also in part how I approached the subject of FI with my wife. At the time I discovered MMM, she was a stay at home mom. I first exposed her to a few of MMM's more innocuous articles, like Frugal vs. Cheap, and Money Does Not Buy Happiness. She was intrigued by some of the articles-- or at least humored me. Then, when we had "the talk" I explained that, while I like my job, I am envious of the time she spends with our daughter and wish that I could spend more time with my wife as well. I don't know that I want to completely stop working early but I want to pursue financial independence so that I can have the freedom to at least work less and spend more time with my wife and daughter. I explained that I truly believe in and support her being a stay at home mom while our daughter is young and requires a high degree of care, but that will not always be the case. I explained that, when our daughter is more independent and in school, I don't think it would be fair for her to be unproductive while I continue to support her and be dependent upon a job. She was understanding of this perspective, perhaps because our roles were once reversed. We now see pursuing FI as the most fair and equitable joint goal we could have-- we both will be productive until we are FI when we are both free to not work. When we are FI, if we choose for one of us to not work while the other works, there will be no room for resentment because we will be working by choice, not because we need to work.
I also spent time talking about what we could do together if we were to FIRE. We both want to travel together and reaching FI will allow us the freedom to do so, so it was easy to paint a picture of the goal-- the freedom of knowing that we are financially secure and the freedom to do what we want to do together. Talking about the fairness of the arrangement, the freedom that financial security brings, and painting a picture of the goal worked well for me.
Part of the reason it worked, though, is that our roles have been reversed in the past and she understood where I was coming from in expecting her to contribute. If you have "the talk" and your spouse/partner does not respond well your expectation that the partner/spouse contribute, it will be very revealing. You will then have some tough choices to make. Here's to hoping it goes well!