Red Honey Gourami Behaviour Change.

Are there any bubbles in the chosen corner? Is that fish chasing the other one? If a male decides he's going to build a bubble nest he will usually choose somewhere the water flow is slowest, like a corner, and spend most of his time there. But that doesn't explain the loss of appetite.

If you look down on the gourami, do its scales stick out like a pine cone?

You could try feeding peas in case it is constipated. Save some peas from your meal, or microwave a few in a container of water for 30 second. Squeeze the insides out of the skin and chop/mash them till the bits are the right size to fit in the fish's mouths. Feed just peas at that feeding.
Be warned that the fish poo will be green for the next couple of days.

Thank Sue, I will give it a try. I don't think it is the bubble nesting cause he has started floating into the open water now, think it may be constipation cause I have had issues with fish and their swim bladders before now and they went the same way, but will keep an eye on him. I lost another red honey a while ago because of aggression, it was too shy and was bullied into not eating. The current red honey having issues is the one who was bullying, so will keep an eye on him for bullying, but it seems to be quiet in there lately.