Yeah, I see that in the big influx of soulmate tropes in romance novels (which I think is being carried over partly from fanfic?) -- that's almost both reactions in one, the spontaneous bam "DAMN you're hot" and "now we are bonded and I must care for you!" (The trope squicks me out personally, but it's interesting.) I think it was sort of implicit in romance novels before -- the heroine is Not Like The Other Trollops the hero seduced (Mr Rochester, &c &c) -- but the fantasy soulmate trope makes it explicit and somewhat essentialist -- it can't be questioned, or denied.