Maria Shriver -- My Christmas Lights Ain't Going NOWHERE

Maria Shriver has no plans to take down those pesky Christmas lights ... even though it's ALREADY APRIL ... telling TMZ, they're way more than just Christmas lights.

TMZ broke the story ... Maria's neighbors have been complaining about the unseasonal decorations outside her Brentwood home, saying they're an eyesore. (TMZ shot video of the lights last week ... and they really do stick out like a sore thumb).

But Maria tells a slightly different story ... and says the lights represent something much deeper than a single holiday, which is why they're still up.

Or maybe she's just making excuses.