driverside inside doorpanel breaking not pieces

The door panels are not available through GM. I went to the Junk yard and found one that was not very good but better than mine on the top of the door panel black plastic strip is stapled to the door panel and on all doors that strip is breaking up (cracks in them where they have been stapled in to the door panel. I have now 140,000 miles on it just found out that the front motor mount, transmission mount, 2 top mounts attached to the top of the Radiator bracket Rack and pinion had to be replaced leaking all the power steering fluid out, still have a GRUNTHING sound when turning the wheel. when taking of from a stop making left turn the whole front end shakes the front bearings have been replaced at 60,k all new struts exhaust manifold by the radiator totally cracked had to replace that in 2015 TPS went out , oil leaks, headlights have water in them had to drill a very small hale on the bottom of the headlights to drain the water out now it is also in the turn signals. I feel that the QUALITY is NOT there any more these are WHAT I CALL PLASTIC CARS WORTHLESS PIECES OF C$%P charge you a RIDICULOUS PRICES and there not worth a DIME NO MORE GM CARS FOR MY FAMILY AND MY SELF.