One thing I've found is that if I drink my urine after 4:30 - 5:00 pm, it keeps me awake at night. I've seen this same reaction from other people in various posts and UT groups I've belonged to. I now make sure I don't drink it after 3:00 pm, and rarely after 4:00 pm.
Chronic insomnia can come from a number of sources. Many people learn simple relaxation techniques or meditation to help with that. I use meditation.