First, no, not guilty at all. Then again, I've been celebrating them for 15 years and even as a JW, we nominally celebrated Thanksgiving anyway.
Second...
Thanksgiving has a bloody history..
Your "analysis" is quite faulty. Thanksgiving has no bloody history. Thanksgiving is pretty much exactly what it's made out to be.
But I was thinking that it's not what someone made them in the past but what they are right now.. to us, at this moment.
That's the rationalization people use to appease their consciouses. The whole reason for celebrating holidays is for the tradition involved. Its meaning, its symbolism, reaching back into the mists of the past are precisely what makes them so important. The pagan origins of some of these holidays are very important. And they should be.
Rather than be afraid of their origins, you should embrace them for what they are. Your rationalization here is a key indicator of your lack of a free mind.
"this meal is a meal in dedication to the slaughter of the Indians."
You apparently have no idea what Thanksgiving is. Having some significant deal of a Cherokee legacy, I'm actually rather offended by this.