It's probably just a male deffending a territory he feels belongs exclusively to him. If you added three or so females things might work out provided you add them all at once and also re-arange the tank and provide some floating and tall-growing plants for cover and to create more possible territories.
Honestly though, if the fish is as aggressive and possessive of its territory as you make it sound, there is absolutely nor eason to get another gourami. It doesn't need company - it obviously preffers to be on its own. Honey gouramies are generaly quite territorial and pretty much solitary fish so keeping them alone is not a problem.
Now if you want another couple of gouramies for other reasons - like if you just like the look of them and want a few more for your tank - not because you want to keep your current fish from feeling lonely, then maybe think about one of the larger colisa species - thick-lipped (colisa labiosa) or banded (colisa fasciata). These should be less at risk of being bullied and chased around by the fish you have right now but are also peaceful enough to get along with and not attack the honey. Pearl gouramies are another option.
Regardless, however, you should specify your tank's size. It may be that the aggression you are observing is directly attributed to limmited space. Another issue with tank size is that you cannot keep the honey with other species of larger gourami if there isn't enough territory space for them. You need at least a 10 gallon for just one more of any larger colisa species and any more than that would require at least a 20. If you want to keep pearls, again, a 20 gallon or more is adviseable.
