The significance of dreams
Have you ever dreamt about your ex or being attacked by spiders? Your subconscious wants to tell you something and uses feelings to do so. Upon waking, your brain will search for the most meaningful images corresponding with those feelings. The challenge is to translate those images.
According to the Jungian method, everything in your dream is a quality of you. The quality, be it a vice or a virtue, which you attribute to a person, animal or even a thing, is all about you. A spider could be the symbol for your creativity, your ex could refer to the non-listening-part, self-centeredness or the male/female side of you.
Of course one could use a dream dictionary to find meanings, but far more interesting are your personal associations. The analysis will give you profound insight into your growth process.