This can be a real,serious problem. Sleep is your body's natural healer and Doctor. Without it, your immune system is greatly compromised. You'll get sick more often. Your metabolism slows and doesn't burn calories efficiently, resulting in weight gain and all the attendant medical problems that that brings. Depression is another risk. Lack of sex drive. It's no joke.
And you can't "catch up" on sleep either. You either get it or you don't. I would seriously check into some kind of sleep therapy or even prescription sleep aids. Another thing you can do it totally black-out the room that you sleep in. Since your body's sleep-readiness is largely influenced by light (your so-called "Circadian rhythm") the light from a computer screen or even mere daylight can put your body in "awake mode" even if you're dead-tired. When I lived in New York, I literally sealed my bedroom windows with both tin foil and black gardening plastic sheet, like a tomb. It must have looked like a vampire lived there, lol. But man, did I sleep well after coming home from overseas and having sleep cycle all screwed up.
Now, the guys all joke about me being able to sleep anywhere, any time. They have photos of me sleeping upright in airports, in the bus seats, sitting up, in dressing rooms on the couches, laying down in locker rooms on the wooden benches. Anywhere I can grab a nap, I use it like therapy. :)