Muscular aches are a common side-effect of statins. If you were to discontinue taking the statin, you would probably see the aches go away.
A well-formulated ketogenic diet should help with your energy levels, provided you eat enough fat to replace the energy lost by curtailing carb intake. This is not actually as scary as it may sound, since it takes only 133.3 g of fat to provide 1200 calories of energy, whereas it take 300 g of carbohydrate to provide that amount of calories.
A well-formulated ketogenic diet is also likely to greatly improve your lipid profile. Too much carbohydrate in the diet raises triglycerides and lowers HDL, and a high ratio of triglycerides to HDL has been shown to accompany a greatly increased cardiovascular risk. On the other hand, a keto diet usually lowers triglycerides significantly and boosts HDL, and a low ratio of triglycerides to HDL (2.0 or less in American units; 0.9 or less in the units used elsewhere in the world) has been shown to correlate very strongly with minimal cardiovascular risk (and LDL level has been shown to be bascially irrelevant).
If your ratio of triglycerides to HDL is low enough, you could probably safely discontinue taking the statin. Bear in mind that people’s lipid results generally look quite wonky during their adjustment to a keto diet, so wait until the six-month mark to see what your lipid numbers are really like on keto.