We've all been here. If you've never been there then, good for you! You're a rare bird.
This happens to me, sometimes. I demotivate myself from guitar, even though I never stop playing it every single day of my life. Eventually, If I want to make guitar my living, I had to learn how to get over this "Stagnation".
Here are some solutions:
Find an enthusiastic teacher! A teacher that shows you new ideas every week will help you revamp your guitar playing! Even just by learning one single scale all over the neck can make you feel refreshed and awesome (I've been there).
Another thing that is often overlooked is rhythm guitar: We all know power chords, you may know all minor, major, major 7th chords, ETC but still must of us forget how fun it can be to know how to play, for example, blues rhythm guitar in so many ways.
The other solution is quite obvious... Slow down and write down what do you want to learn, what is missing, what is making you feel dissatisfied. Then, enjoy YouTube and the Internet.
For example: Pick your top 3 musicians and learn from them. You don't know how to staff read? No problem! There are TABS everywhere! You can even be super specific: Pick your top 10 moments from your top 10 guitar solos and you don't even have to learn the entire solo. You can learn the 10 licks and mix them all together. There are plenty of backing tracks out there for you to put your recently learned licks to practice!
If you want 1 on 1 personal guitar lessons from me, just go to the Guitar Lessons page. :)
Don't forget to have fun!