dreams are not indicators of the future. they are representations of the past sometimes. let me try to describe it.
some nights you dream about sex. its because the final thoughts before you slipped into unconsiousness were about sex.
some nights you have nightmares because those final thoughts were of a scary movie you watched.
each night you have that nightmare its because those final thoughts were the same fear you had before
btw, its impossible to change those final thoughts because they literally are right before you slip into unconsiousness. after your memory has already shut down. if you are a lucid dreamer (you can control your dreams) its possible to keep the consious part of your brain "awake" while the rest of your brain and body go to sleep. then your consious brain is "awake" inside your dream. its pretty much the only way to really control your dreams
ive learnt how to do it. and its 100% worth the time invested
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I thought i knew alot, until someone who knew more told me i didnt.