I’m a married woman, but there’s a guy I’ve been chasing after for months: the Sandman. I want him desperately some nights — and then other evenings I push him away. It’s completely my fault that he’s turned his back on me in bed. Our always-too-short encounters are rarely satisfying because I’m constantly thinking about an errand I forgot to run or a form I need to fill out for my son’s school. (Even Overstock.com and Candy Crush Saga come between us.) Yes, in terms of sleep time, I could — and should — do better.