"Part of it could be more and more people work shift work. Our society in general is shifting more to a 24/7 one.
I work in a hospital so all hours of work is regular for me. That being said If i know I'm not getting home until midnight or 6 am…"
"I second the suggestions above.
But, don't overestimate your feelings. Yes, ask her out. But, perhaps she doesn't want to take it to next step. But, ask her out anyway, you cannot find out if you don't."