I thought about writing something at your last update, because you wrote something about eating better and sleeping less and it seemed that you were surprised it didn't work out. We often think of sleep as an annoyance that gets in the way but it is one of the most fundamental of human needs for staying alive, as well as being one of the things you need for learning. If you rank our basic needs according to how long you can live without them, the first three would be: air, then water, then sleep. You can't rob Peter to pay Paul. Eating better will probably help you sleep better, but it's not going to make a difference of hours in your sleep requirements.
Sleep is one of those things that is barely understood and yet loads of people talk like experts. So I was skeptical when the top of my Kwiziq dashboad said something like: get plenty of sleep because sleep is when your brain lays down memory (or something). However, I found an article from Harvard Medical School which says:
Sleep, learning, and memory are complex phenomena that are not entirely understood. However, animal and human studies suggest that the quantity and quality of sleep have a profound impact on learning and memory. Research suggests that sleep helps learning and memory in two distinct ways. First, a sleep-deprived person cannot focus attention optimally and therefore cannot learn efficiently. Second, sleep itself has a role in the consolidation of memory, which is essential for learning new information.
One of the key points in the article is that a good night sleep doesn't only help us focus better on our learning (which I think most of us know), but is also essential for memory consolidation.
In addition, I wonder if you should keep your focus on the small goals for the time being. Your post of 11 June shows a clear plan of what to study but also vaguely mentions "C-level exams" and then your most recent post unambiguously mentions C2. It seems to me at some point in June the spectre of C2, the realization that C2 is a monumental undertaking, got to you and you decided to go from reasonably fanatical study (over two hours per day in June), which you could just about manage, to the unfeasible. It shouldn't be a surprise that it didn't go as well as you had hoped. Remember when you had a list of courses and you could strike them through as you finished them? Perhaps you would enjoy making a list of the current resources you are working on so that you could cross them off one by one. (Maybe you already have, I only recently got back into the forum).
Regarding your pattern of "Mission, quit mission, mission, quit mission..." etc, that's actually pretty reasonable and normal. I can't remember who it was, but someone on these forums (leosmith I believe) described language learning like a bow wave on a boat. As a boat goes faster a bow wave can build up in front which slows the boat down, so the boat needs to slow down to allow the wave to reduce to allow the boat to proceed. In terms of boating, it's a bit rubbish (instead of slowing down you build a boat with a better bow). But in terms of learning the idea is that you study hard for a period and then take a break. This would be quite a shift in your methodology, but maybe you would benefit from alternate weeks in your study plan: a study week and a native content week. So, for all of your sit-down study time for one week you focus on grammar and vocuabulary (your coursebooks), as well as your creative writing. This is about the "formal study time", so you could use native materials when you are listening on your commute or reading to your children. On the alternate week you would spend your study time reading Bien Dire and watching Buffy (ugh). One result is that the time wouldn't seem so short. In addition, theoretically the week off grammar and vocab would give your brain time to bed down what you learned the week before. Finally, I think at the end of each week you would be looking forward to the next week's activities. It's just a suggestion, and not one that I'm following for my study, but it seems to me it could be a suitable fit for the way you work given the pattern you describe. Basically, turn what you may have previously considered a weakness into a virtue.