"Loveless" is a negative term, so might be a little harder finding a dating company for this one.
Affection in singular would have been great. Affections in plural with the S at the end isn't used as much. That being said .. still not bad as a brand. However I'd think affections.com would be in the relatively affordable range even for a smallish startup (just checked, estibot puts it at about 8k, which is in the same range I was thinking)
I'm not against plural domains, but the plural term should be be used regularly. According to Estibot the singular gets 74k/mth while the plural gets only 1.6k.
That being said .. neither are too bad if you got them a hand reg or cheap drop. I don't really know the dating website market, so can't really give you a better guess.
Not that it matters in any way, but Estibot puts affections.co at $85. You'd definitely be able to get more if you connected with an end user who wanted it ... but again, I'm not sure you'll find one ...