Hello sanguine - playing should be fun, but it is hard to find good/new/fun songs to play if you only listen to commercial pop radio - way too many stupid commercials, stupid tunes, and stupid deejays on 'regular' radio stations.
Chances are, you just haven't heard anything lately that really inspires you like you were when you first started to play - - but there is a cure for that!
If you live near a university, there is probably a campus radio station where they play 'better' music. They may also broadcast some excellent syndicated music programs that focus on music of merit.
One of the best syndicated music programs is "World Cafe with David Dye". The show spotlights new and emerging artists as well as some musicians that are more well known. The show is also syndicated on some Public Radio stations. Here is a link:
<a href="http://www.xpn.org/worldcafe.php" target="_blank">http://www.xpn.org/worldcafe.php</a>
Most college radio stations are also available via web-casts. I often hear great stuff that inspires me to want to learn a song on our local college station (WMSV Mississippi State University).
I also have some thick binders full of great old songs - much of it vintage stuff from the years of my youth. But there is some wonderful stuff that is more current . . . it's just stuff that you probably won't hear on 'regular' radio.
Hope this helps - another idea . . . meet some other folks who play and get together for fun. If you are a musical masturbator (only play with yourself), find some collaborators and have fun playing with each other.
"That darn Pythagorean Comma thing keeps messing me up!"