I think the gap you sense between what you are doing on paper and what you actually feel is due to the fact that you are in a transition state. You are working to become somebody else (an idealized version of yourself, and this is healthy since you are following through by taking steps toward your goals), but you can't just change internally from one month to the next, it is a process that takes time and cementing so there will be a bit of a disconnect from time to time.
The loss of family members, relationships, and certain friends is emphasized even more when you feel this emptiness. Perhaps there is also an element of loneliness. I'm not trying to psychoanalyze you, I can relate to a lot of it. All of these things have a similar component: change. Naturally, people dislike change in favor of what is familiar. But it is through the hard work of change that people form strong characters and reach their goals.
Teddy Roosevelt: “Nothing in the world is worth having or worth doing unless it means effort, pain, difficulty… I have never in my life envied a human being who led an easy life. I have envied a great many people who led difficult lives and led them well.”
And, of course, the classic Nietzsche quote that everybody forgets is Nietzsche: “Out of life’s school of war: what does not kill me makes me stronger.”
We all have our lows. They always pass. Keep pushing through. A day will come where you look back and thank yourself.