Reddit Moment
(media.scored.co)
This phenomenon is called phantom pregnancy. The female mammal's brain has been so inundated with painful, natural hormones urging her to reproduce for so long that her mind has to construct "children" from its environment for relief. So, instead of constant suffering, the female's subconsciousness has effectively murdered its own natural instincts in favor of the absence of the pain that comes from the unmet needs of the deep reproductive urges in her brain.