What does it mean to dream about getting married to an ugly king?

The ugly king in your dream is a metaphor for some sort of authority, particularly a male or patriarchal authority. If the dream was a nightmare or disturbing, that suggests that you feel as if you are destined to be controlled by this authority, and that you don't have other choices. Note that the dream is about the way you are feeling now. It does NOT predict your future or define your destiny.