2003 pontaic Bonneville 3800 series II V6 3.8L

I have a 2003 pontaic bonneville 3800 seriesII v6 superchared 3.8L. Ihave taken my car to the shop 3 times and now it has quit running. Ther was a ticking noise that sounded like it was coming from the engine, so the machanic said I need a new head gasket, which I got. Then I need a new cataliac converter and spark plugs, which was done also, plus a new thermostat, which had a leak. Well the ticking went from loud while driving to very low while driving, plus had a complete oil and filter change done. Fine for a week then when trying to start it, if I let off the gas pedal it will cut off and black smoke is coming out of the back and the battery dies down and have to be charged to start. Now it will not start at all but if I turn the key to on, the radio cuts off then on then off then on and all the car warnings flash on and off like door ajar, check gages soon, and the temp reaches to 200 very hot when it did run. Plus the battery has to be charged and it still will not run, but it stays charged but if u try to start it now you just her a click and nothing.I have spent so much money in this car, dont know what to do next help me please cause im tired thinking about junking it, it has 145000 miles at this time. Please help mother of 4 in need