Aristocrates – I can only reflect back at you what I feel your dream is pointing out.
You wrote you feel your brother is short-sighted as far as love is concerned, and the imagery you add that thought/feeling, is him going on his own way and you trying to stop him to tell or show him something you think/feel he needs to know.
The result is, in your imagination or feelings, that doing what he is doing will lead him to make a bloody mess of his life.
The beautiful part of the dream is, “He looks up at me, smiles slightly, and says, "Say something to cheer me up, brother." I believe the message is that it is pointless trying to slow down his mad rush to be with his new wife, it is better to give him positive support in a way that is not lying.
Good luck.
Tony