I took Ambien on a flight from NYC to Hawaii once. I love Ambien, but this was not a pleasant experience. I suggest in general that one should not do this if one is traveling alone. If I did not have my wife with me, it probably would have been a very embarrassing experience.
After reading this, just for grins and giggles, I thought I would look up the cost of a train ride from Houston to Los Angeles. Guess what? There isn’t one. The journey is 69 hours and nearly 7 hours of that is riding on a bus.
Sorry, folks - I want to ride the train, not the Grey Dog or its equivalent. 
37 hours on the Sunset Limited, but the train runs westbound only Monday/Wednesday/Friday from Houston.
When I was fourteen, I took the train from New Orleans to Sacramento (with a transfer in LA, I believe). I stayed in California for a couple of months and then took the train back to New Orelans but this time through Chicago. The last leg of the trip was on the “City of New Orleans.” Both trips were about two and a half days long. I did get a little bored. Had I been of drinking age, I probably would have enjoyed the bar a little more. As it was, I sat in the sunroom and looked out the window (this was in 1988, before portable DVD players or widescale ownership of laptops). It was still nice. Some old guys taught me how to play spades. I memorized the Hotel California album, Abbey Road, Fables of the Reconstruction, and Reckoning. I read a couple of Stephen King books - Night Shift and the one with the toy monkey on the cover.
ETA: Clothahump, as **Scuba Ben **points out, Houston to LA is a straight shot - no bus unless you need one to get to the train station. I took that line.
Sleep mask? My wife wears one every night. She’s 32, and we do okay, but . . .