Hi!
Welcome to the forum. I don’t think being so hard on yourself is really helping especially when you’re still pretty new to it. How many hours do you allow for sleep btw? 6 hours should be the minimum.
Waking up groggy is normal even with normal sleepers! Then it kinda just goes away by the time you eat breakfast and get revved up to start the day. It is pretty common to mistake this grogginess with lack of sleep because sleep doesn’t work like a switch that turns on or off instantaneously; it’s more like a dimmer and the things you do after waking up will give your body the necessary cues to what’s going on.
You don’t have to follow cbt-i exactly to the tee to expect the results you desire. That means you can “mess up” a bit here and there, like dozing or taking micro naps and it still wouldn’t affect your sleep drive by very much. Just try it. Be willing to explore and take things further from your comfort zone. Don’t just attribute “failure” to anything you did “wrong”, there may be no connection at all.
Feeling sleepy is a surefire way to tell your sleep system is working. It means nothing is wrong. I encourage you to change your mindset in positive ways that will aid your recovery. In the end, you will just stop following sleep rules, you become very relaxed with your sleep schedule, are very open to the idea of staying up later or finding yourself awakening any time of the night. And you don’t lose sleep over sleep anymore because it’s just not worth it. Recovery from insomnia doesn’t mean free from insomnia, it just means those who recovered are a lot more indifferent to future episodes of poor sleep than they used to be. Actually they are much more common than you think and coming to terms with it is what makes all the difference. Good luck to you.