Fans in Australia last week witnessed the horrifying car accident that leaves Dex with severe brain injuries.
"Dex is very distressed," he told TV Week. "He's really vulnerable because of the brain injury and, more than anything, he just really struggles with seeing everyone around him so upset with him.
"After brain injuries people can become quite impulsive and emotional. Dex really struggles. He doesn't want April to have to see him like that. Obviously she's very caring and worried about him - she hangs around his bedside every waking minute - but he doesn't want her to see him in such a bad state."
Cottier added: "It could be permanent - you can never know with brain injuries. Some people can be remarkably better after some months, while some people take years to show any improvement. The full effects don't wear off for a number of years.
"Luckily, he doesn't have too many broken bones, but the main damage for him seems to be mental - which in turn disrupts everything he does.
"He has to learn to walk again, so it's pretty awful. Dex may pull through, but there is a very long road ahead for him."
Home and Away viewers in the UK will have to wait until October for Dex's storyline to play out.