The way I think about this is matching the cash flow to the situation.
This is certainly true and any 50% "reduction" should not be assumed.
As a personal story, DW did not return to w*rk until I had left the military, and she was ready to send our child to daycare. That was six years after we were married.
I took on the "responsibility" (gladly) to cover all expenses for those early years and when she returned to w*rk, we made the decision that we would live on one income (mine), as we had done since our marriage.
As it turned out, some 42 years later, we still follow that same process. I'm the one who covers 99% of household expenses, along with some of "hers" (i.e. car insurance & maintenance), which means that most/all of her income (and future retirement income) is hers to spend as she wishes - mostly in her travels somewhere in the world, multipe trips each year.
If I were to pass first, she would have to cover expenses she never had to worry about and could never cover on her expected income.
Due to that fact, I've decided to delay SS till age 70 (for her benefit), continue life insurance - even though I'm retired (for her benefit), and have more than enough to pass on to her to continue the life "she is acccustomed to" assuming I pass first.
If I were to pass after her, I would need little/nothing to replace her pre/post retirement income.
If I were to pass first, she would have to have many, many multiples of her income to cover our expenses, to continue to live "in the life she is accustomed to".
Planning needs to be more than just a 50-50 split as a standard assumption, IMHO. You really have to look at your shared experience to determine multiple outcomes.
BTW, she's worth it
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