My former high school is debating taking Robert Lee's name out of its name. As a civil war buff Ive read numerous books over my life which almost universally said that Lee wasnt necessarily a racist or huge fan of slavery, rather he was first and foremost a Virginian and supported the Confederacy on those grounds. Living in an ultra-liberal county the new dialogue that is coming forth is that he is a racist, a symbol of racism, and all the bad and trendy things that go along with it. I'm cool with that if its historically and factually sound - that being said it is not consistent with what Ive come to know for the majority of my adult life.
There's a section on the FAQ that covers this to an extent
https://www.reddit.com/r/AskHistorians/wiki/civilwar#wiki_lee
I'd also suggest the "The Lost Cause" section, to see how that correlates with the literature you've read.
https://www.reddit.com/r/AskHistorians/wiki/civilwar#wiki_the_lost_cause
A letter he wrote to NYT
https://mobile.nytimes.com/2017/08/18/us/robert-e-lee-slaves.html
Overlapping
A letter to his wife
http://fair-use.org/robert-e-lee/letter-to-his-wife-on-slavery
WRT letters in general https://www.usnews.com/news/articles/2007/06/24/the-private-thoughts-of-robert-e-lee