We learn a whole lot about the speaker of this poem. This is partly because she starts off telling us about herself as a teeny-weeny little kid, and we watch her as she grows up and gets married. So the poem gives us an insight into her emotional development over the course of her childhood and teenage years.
She starts off as a really shy bride, but then grows to really love her husband. In fact, she loves him so much that she doesn't do a very good job handling the long-distance relationship, once he goes away. She's so sad to be without her sweetheart. Can we blame her?
The point is, we get a sense both of the speaker's love for her hubby and her loneliness and sadness as a result of her separation from him. And we get this insight into her emotions because she speaks in the first person, confessing her feelings to her hubby (and, indirectly, to us).