About once a month I experience bouts of insomnia. It usually lasts only a 4-5 days but the lack of sleep and disrupted sleep cycle really starts to get to me. I’ve tried various sleep aids to help me with this with some minor success. Sleep drugs tend to make me feel really gross in the morning, so I avoid those, but a small dose of melatonin can often get me to sleep. The best thing I’ve tried is weed, unfortunately I don’t have any weed and don’t really know where to get any in Dallas. Fucking prohibition.
Anyway, my insomnia hypothesis is that it is somehow related to my monthly hormone cycle (yes, men get those too). During my periods of insomnia I also tend to have bouts of depression, my sex drive plummets, I get irritable, and my motivation to exercise or do anything productive bottoms out. I guess these could all be symptoms of something else (or each other) but they create this feedback loop that makes matters worse. I just want to sit around like a blob, but that just exacerbates the sleeping problem because I am not exerting any real energy and I’m in a position to take bad naps (throwing off my sleep cycle even more).
I guess I could go see a doctor or something, but at this point it is more of an annoyance than a real problem. It usually passes in a few days and then I’m back to normal for a bit. These cycles were a lot worse in the past when I was dealing with serious suicidal thoughts and was very unhappy with my life, during those times the insomnia pushed me closer and closer to the edge. But now, I just try to make the best of them and use the time awake at night to watch new tv shows (Hannibal is fucking good!), read a book, play video games, make some art, or play video games. I’m rarely really productive, but I find something to do.
Wandering Oak 
I started watching Quantico and am so hooked, it flashes back between a group of wanna-be FBI agents at the academy in Quantico, going through their lessons (psychological and physical stuff where they try to “solve” the point of the lesson) and then present day one of the members is accused of bombing Grand Central Station and her classmates are trying to help clear her name. It’s just….good. So sorry for your sleep troubles! My husband suffers from not being able to stay asleep, and has had issues for about 3 years. It’s hard to watch him go through it, yearning for sleep. I hope you find answers, I know it can be hell and even a few days of hell is unpleasant.