I would say Illidan still has a strong sense of attachment toward Tyrande - he may have broadened this into a sense of an attachment for the whole of Azeroth, but strong specific attachment still remains. It's likely Illidan knows that a pursuit of Tyrande isn't possible (given the measure of her love for his brother) and so indulges himself in other relationships to fill the void, but he hasn't taken any real steps towards shedding himself of those strong romantic feelings as evidenced by his final thoughts on being killed at the summit of the Black Temple.