Nowadays, families are so scattered that going to Grandma's for Thanksgiving is becoming a forgotten tradition, as kids and grandkids start their own tradition of having Thanksgiving at their home. If any are close to you, go to their home for Thanksgiving and take a dish.
If all are too far away, ask some of your single friends who will also be alone on Thanksgiving to come to your home if you love to cook the meal, or name a restaurant you can all go to if you are not up to that anymore. You can check to see if there is a Soup Kitchen or Salvation Army in your area that serves Thanksgiving Dinner to those less fortunate and volunteer to help.
Last, but certainly not least, my favorite suggestion is to go to a local nursing home several months prior to the holiday. Find out from the staff what residents that never have family visits and are capable of traveling short distances. Befriend these folks and, closer to Thanksgiving, invite them to come to your home for Thanksgiving Dinner, with you supplying transportation to and from locations. Get permission from the facility, of course, and check on foods they can and/or cannot have.