Flybiker7000 - Yes, the SAS and the LRDG were major reasons that were assisting in preventing supplies reaching Rommel - but Hitler was also fighting WW2 on 3 fronts by September 1942.
Hitlers primary support was to the Eastern Front, and the German forces in the Middle East were denied the support that Rommel requested at that crucial time - particularly, increased fuel supplies.
The final crushing of the Axis forces in the Middle East came with the Battle of El Alamein, where the Germans and Italians were slowly overwhelmed by the greatly increased force and equipment numbers of the Eighth Army (recently boosted by substantial amounts of U.S. equipment, including Sherman tanks). Increased Allied airpower also played a very big part in the Battle of El Alamein.
Rommel saw what was going to happen long before the Battle of El Alamein and urged Hitler to evacuate all the German troops in the Middle East - but Hitler expressly forbade evacuation, and instructed his forces to entrench themselves and fight.
The final straw for the Axis forces was the sinking at Tobruk, of the Italian oil tanker Tergestea - by Vickers Wellingtons torpedo bombers of 38 Sqdn RAF - and the oil tanker Proserpina, by Bristol Beaufort torpedo bombers of 42 Sqdn RAF.
Rommel noted dejectedly in his diary, that with the sinking of these two oil tankers, it effectively signalled the end of the Axis forces ability to fight in the Middle East.
When the Axis capitulation in the Middle East came, 130,000 Axis troops surrendered and became POW's. This was essentially the major turning point of WW2 for the Allies in their European advance.