Hi again Mik.
I noticed that you're offline and therefore, I will send you an answer now, and if you have any additional questions, just reply back. Thanks!
Spiders in dreams are often viewed as negative symbols because they are seen by so many people as frightening and often represent a controlling force. If your ex-girlfriend has a fear of spiders or other 'creepy crawlies' and insects in her waking life, this could be a 'spillover' into her sleeping/dreaming life. Many times, dreams about spiders can symbolize something about women in general or about a specific controlling woman in her life, like a very strict mother who didn't show much emotion toward her daughter.
Spiders may also symbolize an undesirable or even evil male force; this could be a representation of an overbearing father, lover or boss. If the person dreaming this is in an unsettling position with a job or relationship, they would need to think about if the other person is truly who they represent themselves to be. It could be a warning to the dreamer to listen to their own feelings and instincts.
Someone hiding under the bed, usually a man, is a very common dream/nightmare. This can symbolize that someone in her life was being untruthful and/or she was afraid of the unknown.
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