dreams are based on the last thoughts that go through your mind before slipping into unconsiousness so. this fear you have, has slipped past your mind at the wrong time reoccuringly for a couple years?
get over the fear or somehow settle it within yourself. because obviously its still rooted in your sunconsiousness nd as long as it frightens/unsettles you, you may still expierence nightmares about it
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I thought i knew alot, until someone who knew more told me i didnt.