Seeking my father's WWII military records

I have been trying to find out what happened to my father.  He and my mother married in May, 1943, he was deployed shortly thereafter, and she never saw or heard from him again.  She was never notified by the military that he was dead or missing in action.  He allegedly served in the Army, but I can find no records to support that.  I am 76 years old, have been searching for him 50+ years, and have exhausted every ancestry group and government records available to the public.  Any suggestions as to what to try next will be sincerely appreciated.