I would say jealousy, envy, spite, and in the end, acceptance.
I don't exactly know what you mean by mood. Jacob I Have Loved is written in a contemplative, almost langorous style which fits very well with the historical setting of the small Chesapeake Bay fishing community. There are many themes in this book: life, love, relationships, coming of age, jelousy, and acceptance.
The mood is quite dark and questioning. As the story evolves, the themes change from uncertainty and jealousy to acceptance.