Why do you say "It is better to have loved and lost"?

The logic may work for you. But realize that you are not really in a position to say that because you hae not experienced both situations. This is again like saying I don't like chocolates when you don't even know how it tastes, when the whole world is going crazy about it. I would always prefer to listen to someone who has seen both the situation and then choose the path forward. Love is something which has to be experienced to understand how it affects our life. Not all lovers fall in the stereo type you have painted. Like in any situation there are good and bad examples. Just quoting two bad example and coming to a conclusion is not correct.