[Full disclosure: As of this posting, Susie and I have already discussed the issue privately, and it has been put to rest. However, I still feel that I must address this here as well.]
A phobia that will go to the point of causing physical pain is never ok. It is never acceptable. Something that I did caused Susie this pain and distress whether it was directly or indirectly, and therefore is also not acceptable. In knowing this, I have sincerely apologized to Susie.
As for the issue in general, yes, there are going to be creatures in this game that are associated with phobias. Yes, there will be events where these creatures may spawn en masse, like spiders or snakes. I try to put subtle cues in the announcements when I can to give fair warning. For example, the spider invasion in Serbule. The announcement clearly states hundreds of spiders, so anyone with arachnophobia is going to know to stay away. I will also do the same for snakes moving forward. The show must go on no matter what, but we will try to make sure that everyone is taken care of and informed in these respects. We take this very seriously. If anyone has a concern of this nature that doesn't pertain to what has already been mentioned, please do not hesitate to reach out.