way the islam don't accept the friendship between the boy and the girl

Every person may asking us 
way the islam don't accept the friendship between the boy and the girl 
the most of them think that because the islam count that the boys is a crafty  but because allah know the naturally of women her heart , her emotion , her sensitive to any word that she hear it from boy 
and this isn't fault , on the contrary , this is a big trait that have distinguish women 
because her need it in to be able to patient with her children and bread them and to give them the loving and the emotion 
the women in islam i a daughter , sister and wife she doesn't girl friend 
yes she is friend but for his husband , who would like live with her forever 
how doesn't see any girl but herbut who take here a girlfriend and let her alone