Got it. So, this is likely going to involve some trial and error and it may not make the nightmares go away entirely, but hopefully we can help you find some tools that mean they occupy less mental and emotional space. I would suggest trying to meet with the counselor again, even for just a few sessions, to see if they cam offer support and tools as well. Having intense emotional reactions, like nightmares, around the anniversary of an assault happens to plenty of survivors, so it's possible that this is a situation the counselor has helped someone with before.
As for some other tools, this article has some really concrete steps on handling nightmares that result from trauma:
https://www.livingwell.org.au/managing- ... ightmares/
This article from Pandora's Project is more about dealing with the anniversary of an assault, but some of the tips in there may help as well (that organization is a great resource for survivors):
http://www.pandys.org/articles/copingwi ... aries.html
Looking at those two articles, are there strategies that stand out to you as ones that you'd like to try first?