I would fight back and clear my name. I do not assume that a magical invisible being feels that my life is important enough to directly meddle with it. Therefore, I must control and manage my life on my own. I would work very hard to find out why I was slandered and fix it, preferably through kindness and understanding.
A slanderer does so for just one reason: to get attention. To take power away from slander, the best thing to do is ignore the comments. Otherwise, arguing back with the slanderer just gives it more power. God can sort out the slanderer's karma. I'll take the high road and ignore the person completely or else I'll cause a drama.