Mazda Nothing but problems 2004 Mazda rx-8 since about 40,000 Miles now i have 53,000 still having problems Irvine, California

I have a 2004 Mazda Rx-8 I have owned the car for 3 years and it's been through 2 owners and i have had nothing but problems since i owned it and it started with a O2 Sensor i fixed that and then the radiator and the coolant recover bottle went out and that was a $900 car repair. After that a freeze plug started to leak and since then has 12 check engine light codes. It has cost me more to have the car repaired than the car is worth. All the problems i am having with the car are the same problems you, me and a million other people are having. I want mazda to take care of this and be responsible for their mistake. I recently tried to sell the car "as is" and they wanted to offer me $3500!!!!! Give me advise and help me deal with this!!! Something needs to be done. Help!!!!