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In this novel humans live in an almost jungle like sealed in environment providing for their needs. A few of the inhabitants begin to question where they are and begin to more carefully explore. Eventually a control deck is discovered and they realize where they are at nearly the exact time of the arrival of the star ship at it's destination. If I remember correctly as the ship enters orbit around a planet, it begins to separate into segments in preparation for some sort of transfer to the planet's surface and the story ends there. There were no references to marital status that I remember tho that should not rule it out. I also remember a possible mention of the size of the surviving travelers having deminished over time tho given how much sci fi I read over the years that fact could be bleeding across from another story but maybe not.