HEREIGO- Interesting communication from your mom. Another thing you might tell her to allay her fears is, " Mom I'm the same son, the same guy that you raised to show love to people and show kindness to them , I haven't changed in my personality one bit. But my conscience won't allow me to support injustices I've come to research. I still love you and respect that you remain a JW , there's no reason for our differences to keep us apart."
I agree with Tiki here that your mom is feeling guilt within herself in her " gut feeling " that you are right about the WT Society and I agree that you should keep communication going , but avoid getting into a pissing war with her about JW stuff. Just talk about family, mundane things, weather, how you care about her, her health - but you need to understand that JW's are triggered and trained to defend their faith due to the mind control - if we start arguing or debating with them about the WT Society- we will not win that battle . It's like beating our head on a brick wall due to their deep indoctrination.
And anyway- it's not about winning battles with them or winning debates with them- it's about getting them to eventually THINK about things with an open , free thinking mind. If you haven't read Steve Hassan's 3 books on how to reach loved ones who are under cult mind control I HIGHLY recommend it. His website is : www.freedomofmind.com. His books are also on sale used on Amazon, or other locations on the Internet. It's going to require patience to get your mom to think- but it's worth it- it appears she still loves you and is feeling some guilt and misgivings about your relationship being strained, so now is a great time to do some homework and devise a plan. Give it time bro. Good luck, Peace out, Mr. Flipper