It this REALLY the way it is?

So, I was telling Josh today that I think I have something wrong with me. Physically wrong. I am SOOOO tired. Two weeks ago, I was tired, but I thought I knew the reason. Then last week, I was really excited because I wasn't too tired at all. I thought that the drugs had gotten back into my system and I was no longer having withdrawl symptoms. I stayed up late (happily) more than one night last week.
Yesterday after work, I was ready for bed (which was oh, around 3:30 in the afternoon). I managed to stay up until 9:30 ish, but I was pretty groggy up until then. This morning, I was set to get up early to do my pilates, take Scully (dog) for a walk, have some time alone without squealling children climbing on me (I do enjoy the climbing, it is just nice to have peace too). Anyway, I COULD NOT GET OUT OF BED! I slept until 7:00, took my shower, and then contemplated taking a nap on the couch, even though I barely had time to iron my clothes and walk the dog as it was.
Josh informed me that he feels that tired as well and goes through phases just like I do. His theory is that we just don't get enough QUALITY sleep. (I don't know how he could say that-isn't a 3 year old boy in your face at 3am quality??) So, after 5 more years or so, we will get quality sleep. Until then, we aren't sick. Just tired.