Vietnam veteran, difficulty adjusting to return ( )

Reviewed for VPRC. I got that this was a take on how the Vietnam vets settled into life back in Australia but Johnny Shoebridge's story stumped me for a couple of reasons - the memory/flashback/supposition of Johnny towards the generic fighter Khan ( his enemy) was strange, and his "I have PSTD " but then "I don't" in the real world was hard to grasp and accept.
Johnny has come back from Vietnam and sets off on a road trip to help clear his head before he confronts his girlfriend Jilly and the families of his two best mates who died in Vietnam. On the way he "imagines " the life of his opposing Viet Cong soldier called Khan who also loses two friends and hunts for the girlfriend he lost after the war.
On his travels, Johnny spends time in a sleepy NSW coastal town where he learns the bush is not his enemy. He eventually gets up the nerve to visit the families of his two mates and then finally travel to Carlton to catch up with Jilly.
I found it really hard to accept his musings on Khan. He creates a whole world for this soldier - friends, life in the tunnel, a commanding officer and then life after with non-communist friends and a search for his lost love. I don't think any Vietnam Vet would have felt this way, nor would they have created such an elaborate worls for their enemy in their head . Yes, maybe 20 years down the track , it might have happened but not fresh off the plane!
The book is well written but this stuck with me - it is not plausible. ( )