I think 22 lbs. since January is quite a lot--congratulations! That's losing at a rate of about 1.8 lbs. per week. From what I've read, losing about 1 lbs. to 1.5 lbs. per week and making lifestyle changes (i.e., something you can live with the rest of your life) is a key to maintaining a weight loss.
When you look at eating low-fat, be sure that you get some fat and that it's the "good" fat (like olive oil, avocados, nuts). I remember going to a nutritionist and having her ask me, "Where is the fat in your diet?" We had quite a discussion about how good fat helps you lose weight.
I've heard that pool workouts are wonderful--hope you have fun!
Women who behave rarely make history.