Sorry to hear of your collection of symptoms.
Although classed as rare (less than 1 in 1000) Ezetrol's side effects do include muscle pain, weakness and tenderness. Ezetrol works to lower cholesterol by preventing its absorption from the small intestine.
Statin drugs are more commonly prescribed and work by preventing the manufacture of cholesterol in the liver.
Unfortunately, Statins have a reasonably common effect of causing muscular fatigue and pain too, so you may wish to consider whether asking your Doctor to swap medicines is worthwhile (s/he may have recommended the Ezetrol's for that very reason).
I think at the end of you email you mention a vitamin D deficiency. Many people are at this time of year and a supplement of 400-500iu daily may help lift your mood and immune system, helping your tolerance of the pain and the manufacture of an antibacterial agent called cathelicidin which contributes to immunity.
As food allergies can contribute to muscle fatigue, immune imbalance and eliminatory reactions, such as the post-nasal drip and catarrh you describe, I would recommend the following in addition to the dietary guidelines for fibromyalgia to be found under 'conditions' on our website:
Yarrow complex to aid digestion of problematic foods
Plantago to ease the sinuses and throat
Siberian Ginseng for adrenal support
Sorry to throw a lot at you but I cannot go into great detail here. It may well be worth seeing a registered nutritionist or herbalist for more detailed advice.