I suffer from the same trouble on occasions. I primarily deal with the Microsoft ecosystem which is volatile and fragmented at the best of times.
I would kill to do something in good old java/mysql.
A lot of the new ideas and principles are a mess. Don't get too absorbed - just use what lets you get the job done quickly and efficiently. a lot of it is just noise.
I tend to find that a complete break from everything for a day helps. That and cider :)