You're equivocating here. The short-term infatuation (limerence) is only one aspect of love; deeper love lasts beyond that. But in fact women are genetically programmed to seek and maintain longer relationships, because they have a much larger investment in doing so. Men are more conflicted--they are driven both to spread their seed and to stay in committed relationships, but the latter is possibly more cultural than genetic for males. But all of us may also be genetically programmed to dally a bit. This is well-established and generally accepted science. ⚠️ ↗

"Nevertheless, monogamy, or at least social monogamy, does exist in many societies around the world[46]), and it is important to understand how these marriage systems might have evolved. In any species, there are three main aspects that combine to promote a monogamous mating system: paternal care, resource access, and mate-choice;[38] however, in humans, the main theoretical sources of monogamy are paternal care and extreme ecological stresses.[37] Paternal care should be particularly important in humans due to the extra nutritional requirement of having larger brains and the lengthier developmental period[48][49][50] Therefore, the evolution of monogamy could be a reflection of this increased need for bi-parental care.[48][49][50] Similarly, monogamy should evolve in areas of ecological stress because male reproductive success should be higher if their resources are focused on ensuring offspring survival rather than searching for other mates.[37] However, the evidence does not support these claims.[37] Due to the extreme sociality and increased intelligence of humans, H. sapiens have solved many problems that generally lead to monogamy, such as those mentioned above.[37] For example, monogamy is certainly correlated with paternal care, as shown by Marlowe,[49] but not caused by it because humans diminish the need for bi-parental care through the aide of siblings and other family members in rearing the offspring.[37] Furthermore, human intelligence and material culture allows for better adaptation to different and rougher ecological areas, thus reducing the causation and even correlation of monogamous marriage and extreme climates.[37]"

How else would humans be biologically driven to stay together if not for an emotional investment?