i felt the same thing, watching a ton of youtube, training hours on end, nothing would work.
What i learned:
Don't play to improve, play to have fun, you will improve.
Don't watch many youtube videos on chess. Often you think about high level stuff, but fall vicitim to piece blunders.
Don't care about the elo, if you drop 50 elo it doesn't mean you have gotten worse, its part of the "ride"
If you feel you are getting demotivated, take a break. I didn't play chess for a month at all, and improved my blitz by +550 rating in this singular month
i also loose a lot of games but then i win a lot of games you can chek my history and check my username is barshufskyrocks