Barchester Towers by Anthony Trollope

But there was another visitor at the rectory whose feelings in this unfortunate matter must be somewhat strictly analysed. Mr. Arabin had heard from his friend of the probability of Eleanor's marriage with Mr. Slope with amazement, but not with incredulity. It has been said that he was not in love with Eleanor, and up to this period this certainly had been true. But as soon as he heard that she loved someone else, he began to be very fond of her himself. He did not make up his mind that he wished to have her for his wife; he had never thought of her, and did not now think of her, in connection with himself; but he experienced an inward, indefinable feeling of deep regret, a gnawing sorrow, an unconquerable depression of spirits, and also a species of self-abasement that he -- he, Mr. Arabin -- had not done something to prevent that other he, that vile he whom he so thoroughly despised, from carrying off this sweet prize.

Whatever man may have reached the age of forty unmarried without knowing something of such feelings must have been very successful or else very cold-hearted.