I agree, you're not a fake.. but depressed. Depression tells us all those lies you talk about in your post. Social skills go askew also when we are depressed... and we hold in more than is healthy...and try to stay "within the norm for politeness" while not feeling like it.

It's ok to not respond how you really feel. Don't "beat yourself up about it." It is what it is... depression. But at some point, when you're doing better, you will feel better about yourself to be able to be who you are without feeling guilty... TC