David Gregg resigned his army commission, in a letter dated January 25, 1865: Having for more than three years been on uninterrupted service in the field, commanding cavalry in the Army of the Potomac, I at this time find such an imperative demand for my continued presence at home that my personal attention may be given to pressing private duties and business, that I can no longer defer action to secure my discharge from the service.
David Gregg trak sig ud af hæren i et brev dateret den 25. januar 1865: Efter at have været i uafbrudt tjeneste i felten i mere end tre år som leder af kavaleri i Army of the Potomac, finder jeg det på nuværende tidspunkt det bydende nødvendigt at være hjemme, så min personlige opmærksomhed kan kan rettes mod presserede private opgaver og forretninger, at jeg ikke længere kan udskyde min afsked fra tjenesten.