||Modern economy doesn't need love. Modern economy is hurt by love.
Happy people don't buy so much of things that they don't need. Unhappy people do, if you manage to convince them that the whatever you want them to pay their money for will bring them happiness, love, care, acceptance, or whatever they at the moment crave for. Watch the advertisements for a while, look for the themes where a product or brand is linked with happiness, social acceptance and/or status, love, etc... Advertisement themes are good indicator of what is missing in people's lives.
When the people will start to love each other again, they will be happy again. However, it can't happen, and modern society will ensure it; if it would happen, the quality of life would soar, but - and that for unknown-to-me reasons apparently can't happen - the Economy Performance Indicators would plummet.
It would be interesting to see how much of GNP is caused by a) desire to buy things because of the temporary happiness they offer, and b) because they aren't manufactured for long lifetime anymore (which irks me mightily, but it is a topic for an article on its own).
Otherwise, join the club...