It's easy to 'love' someone you know you'll get something back out of. For example, you might invite more people to your party than your actual close friends, because you know you'll get more presents that way. You only have to spend a few minutes watching TV to notice that it's almost always the rich and glamorous who have flocks of 'friends' around them, that people flock towards the famous. Perhaps our obsession with celebrities is in part down to the idea that if you can get close to them, some of their fame will rub off on you. I'm guilty of trying it too--my brother went to pre-school with the son of the guy who makes VeggieTales :D. What actual relevance that has to anything...
But on an even more basic level, it can mean loving the people who are lovable, being friends to people who you're pretty sure will reciprocate. It's trying to make the input-->output formula work for relationships too, by expecting back what you put in. It's an easy enough trap to fall into. But the Bible says to 'love your enemies, pray for those who hurt you' (Matthew 5 33-34). Now, what are you going to get back from your enemies if you love them? Not a whole lot in the way of nice stuff--probably. Not at first anyway. But prayer does have the power to change things. It's like giving permission to the fairies in Artemis Fowl (now you're going to say you haven't read this brilliant book)--if they don't have the permission, they can't enter a human's dwelling. In the same way, God gave us power over the earth. He can't step in unless we ask him to.
I think the best way to look at this one is to examine your motives within friendships, to wonder why exactly you're inviting that person to your party.
God made you special and he loves you very much.