I agree with the above. Dual mass flywheel most likely worn and needs replacing.

It's next to the clutch. The work involved in replacing the DMF involves taking the clutch out too, so usually if you're doing one, you do the other at the same time (minimal extra labout involved with doing both).

If you've got to ask if it's a big fix, then it's probably a garage job rather than a DIY job.

As to why it needs doing, and what it is ... DMFs are put into (mostly) diesel engined cars to absorb the torque shock to the gearbox. Without a DMF, modern diesels can rip apart the internals of gearboxes. So it's a sacrificial part. As to how long they last, it all depends on how the car is driven, and the type of DMF it is. Different manufacturers use different methods of building DMFs. All wear out eventually, but far cheaper to replace a DMF than a gearbox.

Another of the downsides of modern diesel engined, manual gearboxed cars, I'm afraid.

it only has 58000 miles on it, could it still be that, you would think they last longer than that

Depends how its been driven, ride the clutch (overheating by holding on clutch on hills) or drive it like an idiot as some do hire/pool/company/someone else's car, and the DMF/clutch can be destroyed in very short order.

As RobJP above, DMF is just one of the many pleasures of modern Diesel (and some petrol) manual ownership, especially when you don't know how it's been treated previously.