Antony Beevor mentions this in "D-Day The Battle for Normandy" but didn't go into much detail. He does mention that the stress of combat did result in soldiers on both sides wounding themselves in their extremities (easily survivable) to the extent that the higher ups viewed such wounds as suspicious (German soldiers it seems who had such wounds could be executed, so I guess unlucky for them at times if they were legit wounds).

As I said, sadly he didn't seem to go into a lot of detail on it but he did also mention that battle fatigue did become a huge problem during that time period to the extent that Allied soldiers were being punished for being in aid stations without injuries. Officers and NCOs would be demoted, soldiers would be rounded up and forced out, etc.