I think the old adage 'From complexity comes simplicity' may enter. Love to me is both complex and simple. Love is as simple as me saying (Feel), "I Love . . .", which proclaims so many things. So, thinking what is opposite offers to me there is complexity with that too. Yet, again, there is simplicity when I say (Feel), "I don't Love . . ."
Some words that may offer opposite meanings are:
Indifference as suggested