What does love means? Buddhism teach to love , but when we love someone it's lead to craving , we wanted they must love us too but when things get worse it lead to sorrow. Another thing is we can love ourselves but does it selfishness ? Dose love , kindness , affection lead to sorrow ?
Buddhism explains there are at least three kinds of love: 


raga: lust 
pema: affection 
metta-karuna: unconditional love and compassion. 


The first and second kinds of love lead to sorrow, but not the third kind of love. 

Some readings are:


Piyajatika Sutta: From One Who Is Dear (MN 87), which starts with:


  I have heard that on one occasion the Blessed One was staying near Savatthi at Jeta's Grove, Anathapindika's monastery. Now at that time a certain householder's dear &amp; beloved little son, his only child, had died. Because of his death, the father had no desire to work or to eat. He kept going to the cemetery and crying out, "Where have you gone, my only little child? Where have you gone, my only little child?"

Piyavagga: Affection (from the Dhammapada), which starts with,


  
  Giving himself to things to be shunned and not exerting where exertion is needed, a seeker after pleasures, having given up his true welfare, envies those intent upon theirs.
  Seek no intimacy with the beloved and also not with the unloved, for not to see the beloved and to see the unloved, both are painful.
  

Karaniya Metta Sutta: The Buddha's Words on Loving-Kindness (SN 1.8)
Brahmavihara Sutta: The Sublime Attitudes (AN 10.208)