Sometimes, you just need to live life and gather experience. It is from life that we gather inspiration. The lows and the highs. People can tell if our voice is talking from experience or lying. If you know its lies, that will come across in your voice.
In a made up world, a great deal is reality disguised as yearning. It is the treatment of your characters that also tell a story. That is why so many people abhor Marysues and the like. They are fakey and written by someone without real experience, and after a while, even the writer is not satisfied with the same fare over and over again.