We use it to speak of a wide variety of good things, and of more than a few bad things. Here is how we know love, St. John writes in his first letter. Jesus Christ laid down His life for us. To understand love, Christians look to the cross, where Christ gives Himself away, freely, for the life of the world. What is good is not always nice, and what is nice is not always good.
Love is good, but it can mean crucifixion.
Love means I sacrifice myself for the good of the other person. The cross symbolizes that reality. What is good for the other is paramount to me, and more important that what I might lose in the process of securing the good of the other. I sacrifice myself for the good of the other person. On the night before He died, Christ had supper with His disciples.