I myself had the same feeling.
Motivation goes down, not just at side projects, sport, or work, everything. You just want to be alone, or do nothing or stay with friends? well it’s OK, and perfectly normal.
I had this feeling for the past 2–3 months (holiday helped a bit but it’s also postponing things). I think this is a mix of things: your own pressure to do what you where doing + the fact that you where doing it + you know you should be doing it + other (you pointed some already).
During my holiday I read about “ocupational burnout” and it’s root cause is expectations vs reality. In my case I didn’t know I was burnout until I was really burnt (usually happens that way).
Another way IMO of explaining is braing hangover. I’ve been working like crazy for how long? Super productive, but that doesn’t mean that you can sustain that level forever. I also learned this the hard way.
To me you’re doing a hell lot of stuff, one thing to admire really. Following your doing I opened my Growth Trello board :D. My best advice would be: do 1 thing at a time. For me now is challenging just doing 1 course, staying motivated and trying to start a project.
BTW you said 8 hours, but your calendar shows 10–5 (4–5 I assume is work). You have 1 hour commute :-/ ?
Those are theoretical times, but have you actually recorded those during a solid week? What I found is there’s time you don’t notice (I hardly exit work at the same time for example), shoping, and other stuff. Don’t micromanage yourself it’s bad. Also try to think what really makes you happy. I found that doing things because “I have to do them” not always works for me. And if something you did in the past is not making you happy any more, that’s fine too (open source projects die all the time).
Overall I think we impose so much to ourselves that it may be too much. Looking at some other colleagues in computing, I don’t see them like this or even changing profession and look at other engineers, they work and then go home and have fun.
Most difficult thing is going to be asking yourself and answering yourself on a sincere way what makes you happy, what you want. I found it extremely difficult. Also in my experience (2 years in London), being alone in a city is not easy and despite doing a lot of stuff may help. It doesn’t make it less hard. Be mindful of yourself.
Any case, want to skype or something i’m here :D