Jesus said that it is all very well if we can love those who love us, but to love someone who does not love us, or even hates us to the point where they want to kill us - that is the love that means something to God.
When David Wilkerson started preaching the gospel to the gangs in New York, a group of gang members asked him what he would do if they got their knives out and cut him up. He told them that even if they did that, every single piece of him would continue to love them. That is why he won many of those hardened, drug-addicted gang members to the Lord.
No, not really. It is not necessary to be lovable to be loved. But I do think you have to respond to that love to get anything out of it. Otherwise it's just an emotion that hangs in the air and doesn't accomplish anything.