As another single person, I think you are taking it too far. Sure, its usually no fun to be with a person that no longer sees themselves as an individual, no matter who they are bound too. But at the same time, typically people get married because you know, they like being around that person. A good friend recognizes that and attempts to include that person on a regular basis. Otherwise you are just acting like a jealous kid that doesn't want to share their toys.

Now that doesn't mean you never see somebody alone but it does mean that you choose non-couply activities on an infrequent basis and invite them to those. Then for the rest of the time respect the fact that your friend loves their spouse so surely there is something you can find to like about them as well.