Apparently, lovebirds die when they are alone. Someone told me that they had them as pets once, and when one of their lovebirds died, the other one just had something like a heart attack and died a few moments afterwards. They said they only have one mate in their lifetime as well, which is why they’re called lovebirds.
I looked lovebirds up on wikipedia but it doesn’t say anything about the dying part; but if this is true, then that would be quite amazing.