1997 Chevy Blazer stalls and jerks

At first no problems at all with my truck for over a year, then first and not a big problem the battery dies because I left my phone charging, the next day driving on the parkway at 75 the truck starts jerking, not bad, but noticeable, then it continues in the following days and seems to be worse and worse, most of the time its in 3rd and overdrive either when im coasting or in cruise control, the longer the trip, the worse, also the rpm needle will bounce with no apparent acceleration or revving, also later when I come to a stop it dies, usually starts right back on the first crank but only dies when im sitting still, also the multi function switch needs to be replaced, took it to a mechanic and they changed the spark plugs, wires, distributor cap and rotor button, they said the problem was solved but it continues to get worse whats the deal?