No. There is no macro to do that. Only the Killer can keep the distance, and as you know, it doesn't do the best of jobs in doing so. But that's how it is.
Yes, you get hitted all the time, and the keep distance feature is more so that you avoid one hit here and there, when there are more then one creature, and you walk, and they have to pass one by the other and you avoid a hit or two. But most likely you will always get hitted by the one you are atacking, and specially if you pass by a recently killed corpose, it will stop to loot and you will get multiple hits.
Yes, you get hitted all the time, and the keep distance feature is more so that you avoid one hit here and there, when there are more then one creature, and you walk, and they have to pass one by the other and you avoid a hit or two. But most likely you will always get hitted by the one you are atacking, and specially if you pass by a recently killed corpose, it will stop to loot and you will get multiple hits.