I second working past the anxiety issue first as well. Many people are fat simply because of the culture we live in. It promotes unhealthy food as a time saver and lack of exercise as a labor saver. However, many people are fat due to anxiety issues that may not have anything to do with food.
As fat is less dense then other tissues, the weight issue may be related to the hydrophobia. Fat people are less likely to drown due to lower density, and less likely to freeze to death in cold water due to insulation. Until she believes that the ocean can't harm her, letting go of the excess body fat may be an issue.
No, I'm not being facetious. Go to any Overeating Anonymous meeting and you're as unlikely to hear "I overeat because food tastes good" as you are to see someone drinking a non-diet cola there.
