Why is love banned in 'the giver'?

Question

Why is love banned in 'The Giver' by Lois Lowry?

Answer 1

Even colors are banned! Another thing they got rid of is pain, the real sort. And real pleasure. Nobody's poor, or gets very rich. Everything goes smoothly and predictably; nothing goes wrong that can't be simply talked over and set right.

What they've banned is the real experience of life, above all real individual values, such as love.

Answer 2

It serves no purpose in their society.  Families are just efficient ways to raise children and are dissolved as soon as the children are grown.  Bonds of love would not benefit society, just cause distraction and lost productivity.  Spouses are assigned to avoid the distractions of courtship.