I don't know whatever interpretation you may want to believe of what this verse is saying but when I read it, the first thing that came to my mind was that it was true. Yep, open rebuke is better than love carefully concealed, and the context in which I interpreted this passage was in the context of a person who loves someone namely a guy loves a girl or vice versa and he/she carefully conceals her love for that person in their heart because if they tell them, they may be rebuked and they don't want that and that could be for many reasons. So then, how is this passage true in this context. Surely it would be better to conceal the love and not face the humiliation of rejection? Well the truth is, that in you concealing your love for that person and having no intention in ever telling them will only in the long run ruin you and may even bring you regrets later on. For how do you know that the person doesn't feel the same way? and only if you risk the possibility of rejection then you might be together. What if he/she says no, what effect would that have on you? I guess in one sense it would free you and you can move on therefore the rebuke was to your benefit.
Any ways I don't have the final authority on what this passage means and here are some commentaries from some well known authors
Matthew henry: Plain and faithful rebukes are better, not only than secret hatred, but than love which compliments in sin, to the hurt of the soul.
Jamieson-Fausset-Brown: Secret love-not manifested in acts is useless; and even, if its exhibition by rebukes wounds us, such love is preferable to the frequent (compare Margin), and hence deceitful, kisses of an enemy.
Wesley: Open - When it is needful, in which case, though it put a man to some shame yet it doth him good. Better - More desirable and beneficial. Secret love - Which does not shew itself by friendly actions, and particularly by free and faithful reproof.
Well, I hope from this passage that we may not fear to be rebuked by others but take courage knowing that the rebuke of a Wiseman will only chasten your soul.