It's the anniversary month and unless you have suffered the near loss of a child. So yes,yes I can hate someone one month out of the year. I know,because I experience it.
I asked because you may still suffer but you can't hate someone for one month out of the year. You need to pray and how God how to deal with it. If you have forgiven him still sit with him and if you don't tell him why, and start the healing process from there.