THE MISADVENTURES OF AN ESOTERIC INVESTIGATOR

I think Snape meant it, he had to, but the reason is different. He hated Dumbledore, not because he was good, or against Voldemort, but because he was self-sacrificial. H always did what was right, at whatever personal cost. This goes against all Slytherin traits, especially that of Save Yourself, eff everybody else. He hated Dumbledore for making him, forcing his hand, killing Dumbldore, and securing his position with Voldemort. Snape doesn't want any of this.