Where is my wife at night?

Abigail and I have been happily married (or so I thought?) for 3 years, but lately I come home at night after a long day of foraging and mining and she's nowhere to be seen. Some nights I stay up until nearly 2:00 in the morning waiting for her to walk in and I'm starting to feel like a fool.

Where is she spending her nights? I thought she was the one, but now I'm starting to think she's seeing someone on the side and I'm considering divorce. She's always there when I wake up in the morning but refuses to acknowledge she's been missing for the entire night.

What is a hard working farmer to do?