OK so after reading this thread religiously to try and figure out how to fix this I finally stumbled upon success pretty much by accident. I got a new macbook from my employer and because my Apple Music was not working on my phone I figured I would try and sign in to iTunes and load up my library on my new laptop. After signing in to my Apple ID I noticed that like my phone, my library was showing up empty. The symptoms I was experiencing previously were as follows:
1. If I opened up apple music my library would be empty, or the app would freeze.
2. If I did some of the temp workarounds my library would maybe load but then within a short time all the music would show up as grayed out and would not sync with my account properly.
3. My iMac and Apple TV were working perfectly fine
4. I tried resetting my device, signing in / out of Apple Music and iCloud, turning off iCloud drive, etc
What pointed me in the right direction is that on iTunes on my new Macbook I went into settings and checked the box for iCloud music library and I got an error I could finally deal with. It said I had authorized too many devices for my account. I went to my account in iTunes and noticed that it said I had the max 5 authorized devices for iTunes purchases and 5 devices for iTunes in the Cloud. I then took the following actions:
1. Removed all authorized devices for iTunes in the Cloud and Computer Authoirzations
2. Signed out of Apple Music on my iPhone and turned off Apple Music and iCloud music library
3. Put the phone into airplane mode and rebooted (not sure if necessary)
4. After reboot, opened apple music, turned off airplane mode, and logged back in to my account
5. Went into settings and turned on iCloud Music Library
6. Reopened Apple music and got loading library
7. SUCCESS!
Everything has been working well for a few hours and any glitches I was experiencing before it stopped working completely have gone away. As an iOS developer, I just simply have used a whole bunch of different devices to access iTunes and hit the limit without realizing it which must have put some block / error on my Apple ID that only effected iOS and not Apple TV or iTunes. It's super annoying to me that Apple didn't code in clear error messages when you hit issues like this, which would probably save them plenty of time / energy.
I really hope this solves issues for others, because I know how frustrating this whole experience was for me. Good luck to all!