From my files for my book, "Confederate Colonels: A Biographical Register"--Forsyth was wounded in the hip at Spotsylvania.
He attended the Georgia Military Institute, so he had at least some prewar military training.
He died of a self-inflicted gunshot wound.
He was court martialed twice, once 5-21-63, charges not specified, acquitted.
Once 10-24-64, charges not specified (but probably for refusing to order a charge), found guilty, sentence remitted/disapproved by President Davis. Reinstated 12-10-64. The sources differ on Cedar Creek, some saying he called in ill that day, others that he refused to order a charge and was arrested.