I was just learning about the concept of extensive reading a little while back, and came across this cool website that let's you find media and rank it by difficulty level.
It only supports Japanese, Spanish, German, and Korean for now, and most of the focus seems to be on the former. Still, it seems like a great resource. And it's very easy/fun to jump in and contribute.
I've seen a similar site at https://languageroadmap.com/. It supports way more languages and has lots of media catalogged, but most seem to have no info. As far as I can tell it's kinda dead... but also seems like it'd be really cool if not for that.
To bring it back to discussion - what are some (recent or favorite) books you've read, or shows/movies you've watched in your target language? What are some that you found especially good for learners? And how do you find new material at your level?
When I'm frustrated with immersion, I try to shift my focus from understand-most-of-it to pick-out-something I do understand. From that perspective, I do OK, recognizing some common word pretty often. It's not much, but I'll take any small win I can get. On the flip side, maybe pick out certain words that give you trouble and focus on why.
Also, try going back to easier/repeat material. Going back a few chapters in the book or rewatching beginner videos or rereading level 0 graded readers until you've practically memorized them. I tend to find some material I can look at and say 'this used to be hard, I am making some progress at least!'
Motivation is just hard though, good luck!
As someone who's started and stopped a bunch, I'd say remember the cliche: "The best time to do it was 10 years ago. The second best time is now." Don't let any setbacks distract you from making progress. That effort now opens up future possibilities.