Love is patient, love is kind. It does not envy, it does not boast, it is not proud. It is not rude, it is not self-seeking, it is not easily angered, it keeps no record of wrongs. Love does not delight in evil but rejoices with the truth. It always protects, always trusts, always hopes, always perseveres.
Manipulaton seeks it's own way. It is a way of saying, "My wants are more important than yours, and in fact, they are more important than the relationship itself." No one who manipulates will admit to that, but their actions scream it. Love says, "I value you and will put aside my own desires to do what is best for you."
Love build up relationships. Manipulation tears them apart. One is self-centered. The other is relationship centered. Who wants to be in a relationship with a manipulative person? No one.
Sadly, the person manipulating others will rarely see this. They continue on in their pain, blaming the other (becuase they will not bend to the manipulation) wondering why the relationship doesn't work.