You should check out http://veganyumyum.com/
it has some excellent vegan autum side dishes (roasted squash with thyme, lemon pepper brocollini) which would all be excellent with a hearty main like a nut loaf.
Unless your family has a lot of people who have issues with vegetarians (as opposed to a family of meat eaters where people eat meat because they don't want to be vegetarian) you should be fine serving a meat free meal. In fact, I imagine the family would expect it. In my family about half of us are veg and at xmas every year I always make a different veg main course for the vegetarians that we eat along with the sides that my parents prepare. A lot of the time the meat eaters end up trying to steal the veg meal (hey if your choice was buckwheat crepes stuffed with caramalized onion, roasted portabellos and gruyere cheese and covered in white wine thyme cream sauce or slices of turkey what would any reasonable person choose?).
Just make the meal absolutely great and I doubt anybody will complain about the missing meat.