Witnesses told police they saw the man fire two to three shots toward a nearby building that houses the Barnes and Thornburg law firm, where Mary Jane Frisby was a partner.
"He turned and it's like he looked directly at us and fired two shots," said Anthony Prather, a lawyer who was in the office at the time.
On Dave Frisby's Facebook page, he posted a message, apparently shortly before killing himself, condemning the law firm.
"The bad lawyers at the Barnes and Thornburg law firm ... do not respect the institution of marriage and corrupted my wife Mary Jane (sex and drugs). Someone (maybe one of their good lawyers) please make them pay. Justice demands the truth out. It's a tragedy."
Fribsy, who was armed with two handguns, was pronounced dead at the scene, police said. There were no other reports of injuries.
Frisby's Facebook page lists him as retired from Indiana University Purdue University-Indianapolis.
Frisby is shown at left just moments before turning the gun on himself.
UPDATE: One reader says Mary Jane Frisby had just left the law firm to take a new job at Columbus-based Cummins.