It takes a well balanced person to not be affected by one's foes. It takes a strong person who can ignore one's enemies. It is not easy to disregard the hateful actions from those who hate you. If one is secure in oneself, the actions of others, especially those of foes or enemies, cannot harm one.
While it is sometimes easier to overlook the harmful actions of foes or enemies, it is not as easy to be cautious of loving friends. Although not done so intentionally, loving friends can harm one more easily than an enemy. It hurts when a loving friend betrays one. When one has confidence in a loving friend, it can hurt when betrayal happens. While the betrayal may not have been planned, it hurts still the same.
Kipling writes a didactic poem on how to live a well balanced life. If one can love cautiously, it is a lesson well learned. Be careful not to love too much. It is dangerous to give one's heart away. Enemies and even loving friends can trample it. Guard one's heart. That is Kipling's message. Love cautiously. Live life carefully. Do not allow enemies or loving friends to steal one's joy. One will be a man when one has learned to live by Kipling's instructions:
If you can talk with crowds and keep your virtue,
' Or walk with Kings - nor lose the common touch,
if neither foes nor loving friends can hurt you,
If all men count with you, but none too much;
If you can fill the unforgiving minute
With sixty seconds' worth of distance run,
Yours is the Earth and everything that's in it,
And - which is more - you'll be a Man, my son!