Doesn't sound absurd at all to me. Divorce is bad enough so the child can perceive it as having the same "finality" as death, with additional burden of abandonment, disowning and guilt without any chance of reconciliation.
Katy Faust in "Them Before Us" published in 2021 cites the study making this exact claim: "One study found the death of a parent inflicts less psychological damage on a child than divorce. It appears children fare better when they know their parents didn’t choose to abandon their family." The source link in the book appears to be dead, but searching for the title "Parental Divorce—Worse than Parental Death" surfaces plenty of similar studies, enough to satisfy an inquisitive mind.
Katy Faust in "Them Before Us" published in 2021 cites the study making this exact claim: "One study found the death of a parent inflicts less psychological damage on a child than divorce. It appears children fare better when they know their parents didn’t choose to abandon their family." The source link in the book appears to be dead, but searching for the title "Parental Divorce—Worse than Parental Death" surfaces plenty of similar studies, enough to satisfy an inquisitive mind.