Basically-we are not eating for "two" we are eating for one and about 1/8th.

That is the way it SHOULD be, anyways. Since 2000 calories a day is supposed to be an "average" diet for the average woman maintaining a normal weight-you are supposed to add about 200-300 calories to that in the second and third trimesters of pregnancy. Not eating double what you normally would. So, try to aim for around 2200-2500 per day.
If you are gaining 2.5 pounds per week-or 10 pounds a month-then you are probably way overeating. If you are having problems with feeling hungry-eat low calorie foods with "bulk" to help you feel fuller. Fruit, oatmeal...things that filly you up quickly. You could eat a HUGE bowl of oatmeal for under 300 calories (a double serving) for what a 1/2 cup of premium ice cream, or a candy bar would be-and stay fuller MUCH longer.
I gained about 60 pounds with my first pregnancy-because I ate whatever I wanted, and didn't exercise. I learned my lesson on babies #2 an #3. I watched what I ate, and continued to exercise throughout. I actually taught dance lessons up until I started labor-I had to call my class members and tell them I was dilated to 3cm and in early labor, and that class was cancelled.

With this pregnancy I gained about 45 pounds-but that is much better than the 60 the first time around. 15 pounds is 15 pounds!