Your question reminds me of what the commuters used to ask me when, for the umpteenth time, I'd just authorised the despatch of the mainline train to London two minutes before their branch line connection arrived at our station (thus making them late for work, yet again, and costing them lots of money): "How do you sleep at night, pal?" ;-)
It often takes me several hours to get to sleep. I've never been able to sleep face down (and I fail to understand how anyone can). I also find it hard to sleep on my back. It has to be on my side, but then my hip will start aching, or there will be some other niggling pain to annoy me. When I finally get to sleep, I'm hoping for some good nightmares! (I enjoy waking up, utterly terrified, and covered in sweat, in the same way that some people love fearsome fun fair rides - which I would never go on!).
The neighbour's cat will sometimes sleep at the foot of my bed but, more often, she'll turn up at some horrid hour and start miaowing for food and/or fuss. (My name for her is 'Noisy', with good reason). Irrespective of the cat's presence (or lack of it) I rarely sleep for more than 2 hours without waking. (When I was younger I used to only sleep for around 10 hours per week, usually going for 2 or 3 days without sleep, but I can no longer manage that quite so easily!).
Chris