HELP! I keep dreaming about her. Why is this?

There was this girl I had a mostly online relationship with. She was almost perfect and checked all the boxes in things I was seeking in a woman. She never had a boyfriend, never had a first love, and even never had a male friend before me! I thought she was Godsent.

Anyways, we carried this online relationship for 5 months and then I finally met in person a week after her birthday. She rejected/dumped me that weekend.

Fast forwarding, this past Friday, she married another man. I was devastated. The emotional and psychological pain was so bad, I had to be hospitalized for 7 days. He got to be her first everything!

I am trying to move on, but I keep having dreams about her. Last night, I dreamed I was at her wedding and she was wearing a white wedding dress with a blue head cover.
HELP! I keep dreaming about her. Why is this?
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