It's like two guys on a boat, and one of them is drilling a hole in the bottom. The hole in the ozone layer does not discriminate. Drugs and theft and violence have no boundaries. In order to attain love of humanity, a person has to start with his own family. The healthy psychological progression is to move from love of parents, to siblings, to spouse, and then on to our children.
Marriage is a good training ground.
It teaches you how to identify with another as yourself. There is one love, however, which must precede everything. This means it's not realistic to love your neighbor, unless you love yourself first. If you feel unhappy about yourself, you cannot love others. For the love to be real, it has to flow from yourself outwards.