Welcome to

!
What you are doing right now isn't Atkins, which would be okay if it were some other healthy way of losing weight. But from what you are saying, your diet appears to be low in calories, fat, carbohydrates, vitamins, fiber, etc. thus lacking the nutrients your body needs to maintain its health.
Since you came here, I am assuming you want to follow Atkins and work not only towards a slimmer you, but also towards a healthier you.

I don't know if you have the book or if you can order it on Amazon, but if not, there are sticky threads on top of the "14-day Induction" forum where it is explained how the Induction phase of Atkins should be followed correctly. Atkins does not mean only egg, meat and diary. First of all, Atkins is a high fat, moderate protein, low carbohydrate diet. During the Induction phase, which lasts for a minimum of 14 days, you are allowed to eat a variety of red meat, poultry, fish, shellfish, aged cheeses, vegetables, fats (oil, butter, etc.). You are also allowed to have 10-20 olives, 2-3 tablespoons of lemon juice, some cream, half an avocado, etc. Net carbohydrates (that is, total carbohydrates minus dietary fiber) are limited to no more than 20 grams per day and over half of them should come from vegetables. You are supposed to eat 3 cups of vegetables per day---Atkins without veggies is not Atkins.
Here are links to some of the sticky threads I am talking about
:
http://www.atkinsdietbulletinboard.c...induction.html (What are the Rules of Induction?) http://www.atkinsdietbulletinboard.c...induction.html (What foods can be eaten on Induction?)
You said you are "just giving up". If you have been doing this "egg diet" thing since May, this is not surprising. It's not only that food becomes very boring when all you're eating are egg whites (did you know that it's the yolk that has the most nutrients, not the egg white?), chicken and milk, but after a while your body will start sending emergency signals, asking for more nutrients.
Diet sodas. They are still sweet, so they must be sweetened with something. This "something" is often aspartame or Splenda (sucralose). Dr. Atkins recommended avoiding aspartame whenever possible, as he observed many of his patients were stalled by it. On the other hand, diet sodas sweetened with Splenda are allowed; however they do not count towards your daily water intake (minimum 64 oz) and one serving (8 oz) should be counted as one serving of sweetener (the limit is 3 servings of sweetener per day).
Please read the info in the threads I linked above and tweak your diet so that you reach your goal weight while also improving your health, which is what Atkins is about. By the way, what are your stats (height, goal weight, etc.)?
Are you taking any nutritional supplements? Do you also exercise?