1999 Chevy Suburban Rough Running, misfires?

I have a 99 Suburban with a 5.7 L motor and 107,000 miles. Bought it a few months ago and had no issues 'til lately. Three weeks ago it died and left my wife stranded. Had it towed and the mech said clogged fuel filter. Changed it and it ran fine for about a week. Then it started to run really rough. Took it back and had a full tuneup done. New plugs, wires and rotor. Still runs poorly, maybe even worse. Also, it died on me and wouldn't restart. So I put a new battery in. Now it starts, but runs terrible. SES light is now on.