Why do you think "a person being primed for feeling pain when being separated from their new partner" matters here?
Are you thinking about studies that, at the very least, suggest the possibility of such a separation being an option that the subject will experience based on the outcome of some action/decision being studied? :( that's horrible ):
An objectively verifiable indication that an animal has pair-bonded would be a visible indication of distress when forcibly separated from his/her mate. I'm not suggesting that this is the best way to determine whether an animal has pair-bonded. For example, an elevated level of some hormone in the blood stream (a "being in love" hormone) that reliably indicates being pair-bonded would be a superior objectively verifiable indication (in my opinion) because it doesn't involve causing distress in an animal.
I'm not a biologist - just an occasional recreational reader of popular works in biology. So, my opinion isn't worth much.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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