"Is it just my perception or are more people choosing to kill innocent people whenever a girlfriend dumps them or they feel slighted or under-appreciated?"

Across the board people are under increasing stress. The lack of an effective social safety net and ever increasing social and economic pressures are pushing people closer to the edge. People find it harder to step back and see things in perspective.

Not reacting to an insult is seen as fatal to the reputation. A girl drops them and it seems like the end of the world. There is no inner store of realistic and well found self-worth. For them it is all or nothing.

It takes a strong self-image and sense of self-worth to shrug off an insult and walk away. Inner weakness breeds aggression. This is true at the individual level and in terms of societal violence. From massacres in Vietnam to the mass murder at VPI the violence tends to be committed by people who are overstressed using aggression to cover their fear and lack of inner strength.