Interpretation– He was debating whether to return to a long-term affair. He did not want to leave his wife because of his young daughter. He felt conflicted, but felt that his life was entwined with the woman he was having an affair with. He thought it was likely that he would not stay married to his wife if he did not have some outlet for his sexuality.
Horses often represent female sexual power. The wife in his dream was his emotions, as a significant female partner and especially a wife represents primary current emotions. In dreams, a person, animal, or spirit is a part of the dreamer’s psyche. Men tend to go with actions while women go more often with emotional parts of the mind.
Water is almost invariably emotion in dreams, and urine is negative emotions. The dream is screaming that he is forcing himself to endure negative emotions to experience female sexual power (the horse). There is a price to pay emotionally for being involved in the affair.
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