Does a fear necessarily have to be based on danger or harm?

Many times I find myself “defending” my fear of spiders. I tell people I am afraid of spiders and then people tell me that I shouldn’t be afraid of them because most of them are not dangerous. It even happened in my psych class, my friend rather rudely stated that people who are afraid of spiders don’t make sense.

I know that they’re not dangerous for the most part. I’ve never even been bitten by one. My fear of them doesn’t come from a fear of danger or death. I am simply frightened by their shape and their movements and everything about them. It also grosses me out, if fear and disgust can be linked. I cannot even look at pictures of spiders. Typing “spider” on Google images really freaks me out.

I don’t really understand where this fear comes from. Does this make any kind of sense to anyone?