Fat takes a lot of energy to digest, and will slow the digestion of carbohydrates. Carbohydrates will raise your insulin levels like no nothing else (especially high glycemic index ones) When a person's insulin levels are high, they can not utilize stored fat for energy as readily. They can, however use carbohydrates that have just been ingested. This leads to the common misconception that without carbohydrates, we wouldn't have any energy. In a culture where everyone eats cereal, bread, pasta, sugar, etc like it's going out of style, everyone has elevated insulin levels and nobody can have energy without their carb blasts.
my advice to you is to reduce carbs and increase fat even more, and maximize your nutrition, as many nutrients, namely b vitamins are needed for the metabolization of fat for energy, and all nutrients impact the functions of other ones in some way or another. After a week or two of this if it isn't working out, get a metabolic typing test (research metabolic typing). Some people, although not many, are just not cut out for low carb, high fat diets (as much as people around here deny it).
But when you say that you "try to eat more fat" that tells me that you still are getting a significant portion of your calories from carbohydrates, and your insulin levels are too high. Play around with it a little bit. Try 30% carbs then 20% carbs, then maybe 10% carbs if those aren't good. Give each one a few days starting with 30% first and moving downward.
Stabbing conventional wisdom in its face.
Anyone who wants to talk nutrition should PM me!