Stay the course, make sure to add plenty of salt to your food. As Alexx99 stated, your body is going through a lot of changes. For many, many years your body used glucose as its primary source of energy. You are now not giving it that source of energy, instead giving it fat to use but it is still in the process of making changes to be able to use that fat as fuel, hence the low energy and foggy brain. When you are hungry, eat fat. Eating more carbs may delay the process of becoming fat adapted.
Also as Alex99 stated, you should work with your MD to monitor any meds you are taking that are associated with T2D as I have heard that the need for insulin can go down fairly quickly.
Hormones also can throw a monkey wrench into the works, especially for us women.
For the first month or 2, just eat when hungry, keep carbs below 20g, don’t go crazy on protein, don’t weigh yourself (the scale can be all over the place and you could actually gain a little weight as your body adjusts. Those first 12 lbs you lost were mostly water weight, because when you eat carbs, your body retains water. When you don’t eat carbs, your body flushes out the water), increase your salt, make sure you drink enough water (take your weight, divide by 2 and that is how many ounces you should be drinking per day plus a little more if you are a coffee or tea drinker), don’t worry about exercising just yet, and wait until you are fat adapted to incorporate fasting into your routine (if you want to that is. Intermittent or extended fasting is not a requirement. People tend to naturally start to intermittent fast naturally because of increased satiety from the foods they eat)
If you can get through the adaptation period, which I know you can, then you will be feeling so much better, a lot more energy, decreased hunger, brain fog will lift, hormone regulation, and blood sugar control (you may want to invest in a glucose blood meter if you don’t already have it). This is the hardest part of going keto.