Our pump is half an inch off the ground as the original plumber who installed it said that was the best way to avoid vibration etc. So the pipes each carry a quarter of the weight of the small pump. Perhaps this was part of the problem, even though it has lasted for many years ok?
Whilst your plumber was thinking about you when looking to minimise vibration, unfortunately he went the wrong way about it.
That's why the couplings keep breaking, it needs to be installed correctly, flat on the floor on it's rubber base/feet, not suspended in the air by them. They are a testament to well made hoses that they lasted that long but wouldn't last forever.
As Dean recommends, 2 full bore valves on the inlets to the pump will allow it to be isolated any time it is to be left for long periods of time if needed for your piece of mind. Try and avoid using the valves on the pipes if you can.