CarHop ripping me off Fort Worth, Texas

I fianced my car from carhop.last year on septmber 13th, today made a year I had this car.the first month I got it the thermostat went out.then the next following month had a problem with an oil leak,they sent me to two of their mechanic shops and neither one fix it.so I driving with an oil leak for an year until three weeks ago when they sent me to aamaco and they finally fix it.then I start having problems with battery light constantlly staying on ended up buying two batteries on two differnt occassions then had to turn around and replace an alternator and paying someone out of pocket for it.now I'm having the same problem and tonite on my way home from work sound like the motor done start knocking.they want let me trade me cause I still owe at least 45...00 dollars on it.I need an dependable car to get back and forth to work.they don't want to help me but they want their payments ontime every two weeks.I'm scared to drive on the freeway because it might just break down in minute now.can you please help me.