What follows treats love as consisting entirely of desires and motivational profile:
x loves y just in case x desires goods for y up to and greater than what x takes y to deserve
We might have as a dual:
x hates y just in case x desires bad for y up to a greater than what x takes y to deserve
Clarification 1: When John loves Sally, John wants good things to happen to Sally in general. John might want goods for Sally even if John isn't involved in Sally obtaining said goods.
Clarification 2: When John merely likes Sally, John wants good things for Sally that Sally deserves. Note, John not wanting Sally to receive goods greater than what John thinks Sally deserves is not equivalent to John wanting Sally to not receive goods greater than what John thinks Sally deserves. The latter - but not the former - would lead to John being upset if Sally did receive such goods.
Clarification 3: One might hold - as Velleman does - that John desires goods for Sally out of respect for her capacity for practical reasoning. I would not accept this though. It seems to me love for another person is love of that other person's qualities, because that's all there is to the other person. I can't imagine a table absent extension, color, shape, etc.; I can't imagine Sally absent all her qualities, so how could I love such a thing?
Response 1: If one loves another only for their qualities, then since these qualities can be instantiated elsewhere, the beloved is not unique, and that seems counterintuitive.
Rejoinder: While true qualities can be instantiated elsewhere, quality combinations are rarer. There are many blue-eyed individuals, but fewer blue-eyed brown-haired individuals. Attending to the configuration of a beloved sharply restricts the likelihood of another individual exhibiting the same quality set. Moreover, everyone has a height, but each person has a specific height. For each quality, each person has both a determinable and determinate aspects. Focusing on the determinate aspect sharply restricts the likelihood of another exhibiting the same determinate quality set. It is not simply that Sally has blue eyes, brown hair, etc., but that Sally has this shade, hue, and saturation, along with her many other features, which make her rather rare.
Response 2: If a beloved perished but all the beloved's qualities were found in a duplicate, would we love the duplicate? Likely not, so there must be something beyond the mere qualities.
Rejoinder: I’m not sure what to make of this exotic thought experiment, but I’m inclined to say – if all the properties are the same, including memories, etc. – then ‘yes’. Cp. Hurka who asks if our beloved is replaced with a clone with all the same properties would we still feel a sense of loss. He infers from answering this affirmatively that there is something special about the beloved beyond properties. I think this inference is fallacious. Of course I’d still feel a sense of loss, someone has died. Death is a loss. This doesn’t yet show there’s something beyond the properties of my beloved.
Clarification 4: Some qualities we dislike are found in those we love. John might dislike when others interrupt him in general, but dislike it much less when one interrupts him in a charismatic or charming manner. Similarly, things we dislike in general we might even enjoy if done by our lover because we generally like when things are done, say, cleverly or charismatically, and we find our lover clever or charismatic.