Love never stops loving, but love can be forced to walk away in order to remain love. Love's primary goal is doing what is best for others without regard for itself. Allowing others to manipulate or harm people for their own gain is not loving them. It's enabling their own destruction. It's important to remember it's not what people do, but why they do it that determines whether or not love rules their life. If we believe someone is using us for their gain without regard for us, we are not loving them by allowing it.
1 Corinthians 13:4-7 would define it. Kindly read it.
May the force be with us.