Replace the 1/2 & 1/2 with heavy cream. Some people also have a high "metabolic resistance", which you may have. For those with this problem, Dr. Atkins suggests the following supplements to help you overcome this problem: L-carnitine 500mg-3 times daily before meals- this helps ensure fat turns to fuel, and Co-enzyme Q10 (CoQ10) 100mg daily- it helps mobilize fat and is good for heart health. Both of these can be easily found at a health food store, GNC, or often pharmacies in the vitamin section. Calcium supplements are also good in general, and recent studies show a calcium rich diet can aid in weight loss. Hope this helps you get past the problems you're having.
God Bless,
Amy-Lynne