The real problem with love, at least on the human sense, is that everything about it is conditional. Literally, every single thing about human love has conditions. God is clearly different, since it doesn't matter how much we sin, it doesn't matter if we refuse Him, because He will still love us unconditionally. Human love is not the same, and it never ever will be. That changed the minute Adam and Eve ate from the tree and got kicked out of Eden.
Name me anything you mentioned that isn't conditional. Trust... would you trust someone that cheated on you? Trust is destroyed after that, and trust isn't something you earn. It is something you can only lose, and so therefore, once someone breaks your trust, it is practically gone forever, despite if you forgive them or not. Selflessness... that is another aspect of human nature that just doesn't fit. Nobody is truly selfless, and nobody has ever been truly selfless beyond Jesus. You simply wont find it, because it doesn't truly exist. People who are selfless for another do it for a reason. If I have a wife that I love, I would die for her, but explain to me why I would die for her again? It is because I love her, but beyond that, she is my wife. If she died, I lose someone close and precious to me. Not many people would die for random strangers. Even people that would die for Christ, they do so with the knowledge that they will be rewarded in heaven. It is never unconditional. If Jesus said that if you die for Him, you will go to hell, nobody in their right minds would die for Him. Think of it in those terms, and you'll see what I mean.
Human love is never the full answer for anything, because it always has reasons and boundaries and conditions that have to be met first, and those conditions may change over time, but they still all have to be met for someone to stay in love.