Confederate Prisoners after Battle of Chattanooga, September-November 1863.

It is recorded by Shelby Foote and others in books, diaries and periodicals of the time, when Confederates were captured and asked why they were fighting their unequivocal answer every single time was, "Because YOU'RE here." 

You have NO reason to be ashamed of your Confederate ancestors. They fought because the South was INVADED. Period.