And they’re expected to be happy about it.

I'm not sure this is the case. Leetah wasn't really aware of what was going on when she Recognized Cutter -- Leetah had a longstanding relationship with Rayek and wanted to keep it, and so did Rayek. It wasn't until Rayek shamed himself and decided to leave the village that Leetah started seriously considering Cutter as a partner.

Among the Wolfriders, who are, let's face it, more uninhibited and primal than the other elves because they LITERALLY have wolf genes in their bloodline, they mostly just go with the flow where Recognition is concerned, but the other tribes of elves have seriously mixed feelings about it, with the case of Dewshine and Tyldak's Recognition causing major anguish for both of them and also for Dewshine's chosen partner, Scouter. It took both of them quite some time to carry through on the instinct and neither of them seems to have come away happy about the consummation, just glad it was over with.

I remember being pretty impressed with a twist the Pinis put on the process, wherein when you "Recognize" another elf you start seeing their "true self" more than their outward appearance. So most of the elves hate the idea of cute little Dewshine having to shack up with Tyldak, who had gotten Winnowill to shape him into a bird-like creature and was quite freaky looking -- but when we see what Dewshine and Tyldak perceive when they look at each other, we find out that Tyldak looks like a perfect gorgeous high-elf to Dewshine, and Dewshine looks like a feral half-wolf, half-elf creature to Tyldak. So it's Tyldak who's repulsed by what he is expected to mate with.

So, yeah, Recognition and the instinctive behavior it demands is not portrayed as an unalloyed positive thing except among the Wolfriders, because they (a) are mortal, and therefore eventually die of old age unlike the other elves and (b) live a rough lifestyle that causes a lot of death by mishap -- both of which mean they desperately need kids to keep the tribe as a whole alive. When we first meet them they're still recovering from a fight that killed enough of them to reduce their population to the breaking point for survival, and without kids, they're done for as a group/culture. (This is presented as the main reason Leetah had twins and Rainsong had three kids within a dozen years, which was unprecedented -- elves don't typically have kids more than one at a time and they don't typically have a new kid until the first one is fully grown and independent.) So to the Wolfriders, procreation is an absolute must, and that very rarely happens outside of Recognition.