You need to be proud of what great things you have accomplished so far -- quitting smoking is a biggie in my mind (another former smoker here); and you have lost quite a bit of weight already. Coming back here is another one -- becuz it means you are aware and are taking action ...
Whatever plan works for you is the best plan for you. Sam Grossman wrote a book called FIGHTING THE FOOD FIGHT in which he applauds the comfort & ease of eating similar things most days; it's simpler and lots of people already do that.
My main motivation is GOOD HEALTH; it is one that never fades, never leaves you, and never diminishes in my mind. You will benefit later on from doing this now, even preventing health problems related to excess weight. That's the best motivation in my books, anyways.
Do you have a community gym in your area; they are often cheaper, have one-on-one help, and have ladies clubs too. Walking is the best and cheapest exercise of all; and you can do hand-weights at home -- about 3 times a week is good.
I would also recommend a basic vitamin + minerals supplement daily with the plan you are using; actually, I recommend that to everyone to make sure they are getting all the basic nutrients they need each day while losing weight. I agree that losing slowly is the best method; your body is less likely to panic that way.
About the pop issue; that alone could help lose weight, esp since you drink so much of it. How about cutting down at least (have 1 glass a day), then out after a while -- keeping the sweet tea instead. 3 liters of sweetened pop a day adds up to a lot of calories: that's over 1000 calories a day just there. If you just cut that out and nothing else, you could lose 2 lbs a week!
Something to think about, eh?