Journalists here have been spotlighting the online harassment of MPs and its possible relationship to the parties themselves and to the media. The tribal bombast with which the tabloids have been treating Brexit has been blamed for its part in this by Harriet Harman and Diane Abbott, among others. The argument is that hostile coverage both encourages and "normalises" vitriol against politicians.
This is fairly astute conclusion in my opinion. I think it would be an unlikely coincidence that people being referred to in these three DM headlines have received floods of threats and abuse from people calling them traitors who should be various expelled from government, hanged, or raped.
The Daily Mail itself recently ran a headline about the abuse that one unnamed Conservative MP allegedly received from what it describes as "Corbyn's trolls". Now, this is not at all sufficiently substantiated, but pretty plausible. Elements of Corbyn's harder left wing support have form for harassing their political opponents both online and off. Labour's leadership elections were marred by this sort of behaviour.
This could really be regarded as another dimension of the frightening acceptance our society as a whole seems to have for using social media to write disgusting things about or to people, but there may be some more significance here, given the fact that (most of) these people are elected to represent the interests of their constituents. These people potentially being influenced by threats and coercion is the whole nation's problem.