The titular "wife," our narrator and protagonist, begins the poem with a brief discussion of her present plight. Her thoughts on this situation, in so many words, can be summarized as "Holy hockey pucks, I'm really sad—like, sadder that I have ever been. Woe is me, sadness, sad, I am so sad, gonna put Hallelujah on the stereo and cry my eyes out, kind of sad."
So yeah, that's pretty… sad. Why so down, you wonder? Well, it's a long story. Here's the gist:
The wife explains that her "lord"—her husband, and also possibly the lord of her people—left their community for a distant land. It's unclear if he was exiled, or left voluntarily. She decides to set off to find him, a "friendless exile" in her journey. Her plans of successfully rejoining her husband, however, are thwarted by her husband's kinsmen.
She is then commanded to live in a hole in the ground. We don't mean a run-down apartment. Nope, this is pretty much a literal hole in the ground, from the looks of the original Old English. Here, in exile, she is completely alone. She has nothing but her many sorrows to keep her company, and apparently nothing better to do than to write elegies lamenting her profoundly sad story. Thanks for sharing, wife—we really needed the morale booster.