Welcome Sionra
The topic has to some degree been discussed earlier - follow the link below.
PTSD and other mental issues was not recogniezed at the time as illness, so I guess
many would, as Patton did, see mental issues as weekness. Also I think that it was when the story hit the press it spinned out of control, because of course the signs of PTSD was well know from veterans from WW1.
Furthermore I think Patton was the old school soldier, trying to motivate his troops by his personal presence in the frontline, and by being tough and harsh. More modern mamagement was already on the way (eg Eisenhower), so I guess Patton was unprepared and surprised by the public uproar.
In the Patton movie is says that Eisenhower overruled Bradley in deciding that Patton should go to Normandy. Eisenhower needed a tough solider, while Bradly was concerned for PR