I have been on Simvastatine (10 mg per night )for the last 3 years. My total cholestrol is now 211, LDL 128, HDL 25 and Triglyceride 288. My Fasting Blood Sugar is 97. I am male and 49 years old. My doctor has prescribed Gemfibrozil 450mg tablets ( one per day ). As our doctors here in Iran are usually not updated I always refer to the internet to find about interactions. This is what I found in one site. The same story is repeated in many sites and even University sites.

According to drugdigest.org :
"SIMVASTATIN may interact with GEMFIBROZIL (in Gemfibrozil Tablets)
 
Although the cause of this potential interaction is not clearly understood, using gemfibrozil and simvastatin at the same time could cause a serious or potentially life-threatening side effect that involves the destruction of muscle tissue and could lead to kidney failure. These drugs should generally not be used together unless your doctor is monitoring you closely."
My question is :
What does "together" exactly mean when we speak about drug interactions? Does this mean that I should not take Gemfibrozil for the whole period I am on Simvastatine? Or it means they can be taken with an interval of say 5-6 hours, e.g. one taken in lunchtime and the other after dinner? The physisists here say the interval solves the problem but I can't trust them. The Two guys I talked to were rejecting any interactions between the two drugs before I showed them the  literature on the web.
Thanks in advance to anybody taking time in answering my question.