Sometimes you hate the person so much that you know you're going to dream about them all night long.
Sometimes you imagine what you'd say to them if you saw them again, something like: Enjoy your future finding women who appreciate ____________ , _____________ and terrible ___________! etc.
Sometimes you can't believe you lasted through the hatred for so long. You can, I think, physically feel when someone hates you that strongly, they don't need to verbalize it. It touches everything between you. It colours you both.