Discuss the issues all you want, but do not make it personal.
Many Christians equate the use of the “anti” word by Mormons to be inflammatory and derrogatory much like the “n” word is to African Americans. http://blog.mrm.org/
It is definitely a way of denigrating anything that someone who is opposed to Mormonism has to say. I wish you could see a way to make them stop using it, but I’m sure you won’t since it probably doesn’t have the heightened slur to you as it has to us that are ex-Mormons. I suppose you wouldn’t understand.
Again, I am just trying to point out that quite often these defenders of Mormonism are using an inflammatory word that is quite offensive and yet it slips by your radar without your knowing.