Since you have platinum status, you can use your points to help pay the maintenance fees, although their benefits directory hints that they might take away that benefit. The benefits directory is online at:
https://cmsprod.diamondresorts.com/sites/default/files/US-Member-Benefits-Directory_12.pdf
It describes many ways you can use your points, so you should never have to let them expire.
I am among the many TUG members who bought from the developer before discovering TUG. We bought in 2004 before Diamond Resorts bought out Sunterra. We have passed through the 5 stages of grief and are now at Acceptance. We enjoy the DRI properties, especially the Point at Poipu and Kaanapali Beach Club, both of which are in the Hawaii Collection. The money is gone, but we're making the best of what we bought.