The opposite of love is not hate, it's indifference. The opposite of art is not ugliness, it's indifference. The opposite of faith is not heresy, it's indifference. And the opposite of life is not death, it's indifference.
Love and hate are two sides of the same coin…both require passion and in that respect they are extremely similar. In the same way that extremes of the left and the right in politics are remarkably similar in their vehemence and hatred of each other. Relationship breakdowns usually occur not because love turns to hate, but because interest wanes and love turns to indifference. In that respect I can see how you could assert that the opposite of love is indifference.
In respect of the other examples you cite…I don’t think there is an opposite to art unless you mean a lack of appreciation for art and you’re calling that indifference..not really the same thing, I don’t think the opposite of faith is either heresy or indifference, I think its self reliance. The opposite of life is nothingness.
So hate, art, faith, and life are all the same thing? They must have an equivalence if they are to have the same opposite. I think the opposite of hate is calm (which is what we seek--not love) and disagree, with some, that hate must be learnt. Humans are an animal and all animals express levels of favoritism within their own species. Mating rituals are a big example for favor/disfavor and hate is just a human form of disfavor. Being a violent species makes it worse.