Why won't my iPod connect to iTunes after my upgrade to Spotify Unlimited

I'm really confused why my having Spotify Unlimited impacts my iPod and connection to iTunes. It's really frustrating. I updated from the free Spotify to unlimited 2 days ago, and since then I haven't been able to connect my iPod to iTunes, despite deliberately NOT syching my iPod to Spotify and not linking my local files. I uninstalled Spotify last night and was able to connect iPod to iTunes just fine this morning. I then reinstalled Spotify, and the same thing is happening. Also, I'm seeing my iTunes playlists in Spotify.

I just want Spotify to be Spotify, on its own, with no link to my iTunes. And I want my iTunes to be iTunes, where I can plug in my iPod, move music on/off, add sycn my podcasts. Seems I can't do this so long as I have Spotify, and I just don't get it. Everything was fine until I gave Spotify $4.99.

Please help!