I think that 'who' is not good here because it is in front of a preposition. 'whom' seems to be grammatically ok. A paper I've been reading is written as following.
Who? or Whom? which is correct here?
Jocelyn, having such a peculiar propensity, goes from London back to the Isle of Slingers, his homeland, and then sees that “the Well-Beloved” abides in Avice the First, from who he has to keep his distance because of the island’s custom regarding premarital sex and the deeply rooted differences in their understandings and attitudes toward sexuality.