Nonviolence and ahimsa are equivalent to NAP (non-aggression principle). It's about striving to live without creating harm because you don't need to. Not to create violence and violate others because we don't need to. We can be better.

Attempting to deny such goals through absolutist thinking is a failure the part of those who want to accept that nonviolence, ahima, or veganism has to comply with absolutism in order for it to be valid. Just like "willusionists" deny freedom or free will exists because it can't be absolute. Degrees of harm and not-doing-harm apply. Degrees of freedom. We can choose to learn about what we are doing, recognize the wrong, and find another way.

Harm other human animals? Harm other nonhuman animals? Harm bacteria? What life are we even talking about? I consider psychological life of animals that feel and think to a different degree than us, as warranting consideration for our harm towards them. We are psychologically and emotionally connectable, people have animal companions they love and care for because it's a real connection that is reciprocal and feeds-back for both. Once that reality is recognized, then we can see how other animals are like us in kind and differ in degree, deserving to be free from our harming them. Why? Because we can. Because it's better to not harm, than to harm.

Thinking that because we can't "absolutely" stop harm in "all" aspects, that those who strive to stop and reduce harm are "delusional", is actually the deluded thought process. Why stop engaging in slavery of other humans since we can't stop all harm. Living by the principle of doing no harm is just a delusion, why bother to care about the harm we do or try to stop it! ... LMAO. Have fun on that ride.

Also, the X and opposite-X model as applying to "everything", is more absolutist thinking. To clarify one point "love" is a watered down word, when we mean "like". We like one thing, and can dislike the opposite. Can is the important thing to note. Not that there's always the thing we like and it's opposite value. I can like bananas, or "love" them, but there isn't an opposite to hate or dislike.

saying 'I love X' is just another way of saying 'I hate not-X.'

Claiming "We love only to the extent that we hate the opposite of what we love." is false. Sure you can love truth and hate falsity. Love love and hate hate. Ok. But you loving someone doesn't mean you have to hate someone else. I love X, doesn't mean I hate not-X lol. I love person X, doesn't mean I hate person not-X. I love this persons glasses (X), doesn't mean I hate persons who don't have these glasses, or have no-glasses (no-X).

That's because every positive value necessitates the existence of its antithetical 'evil twin': every parent can be turned into the executioner of his child's killer, every property-owner into an oppressor of the labor class, every Christian into a witch-hunter.

Each positive value has a negative correspondence in many cases. Hot to cold, up to down, left to right, true to false. But affirming favor for one doesn't mean being in opposition to the other.

I get you had this bone to pick with "universal love" and other things ;) but you got lost in trying to explain it clearly ;)

This was like people who try to say good is like light, and evil is like dark, so you need both good and evil. Analogies only carry over so far. Correspondence is not to be carried out blindly after some similarly is detected. Right and wrong, or good and evil, are only metaphorically like light and dark. All the qualities don't apply form one dual model (light/dark) to the other dual model (right/wrong). One is the contrast to the other, to distinguish them, but they both are not required to be created. Something right, good and true can be created without the creation of its opposite wrong, evil and false. The words are descriptors for comparison to know one thing from another: the law of identity, logic.

Similarly, one can care for someone, or values they have, or qualities they have, or qualities in reality, without hating the opposite. Like the color green. Liking Green doesn't mean you hate magenta. You can love the quality or value X, without hating the not-X quality or value. Sometimes there is a clear analogous correspondence of X and not-X applying to love/hate, but not always like you claim. I hope you will consider this criticism of your thinking :) Peace.