Habituation to system changes: the Audiophiles' curse...

I've made a lot of great upgrades to my system in the past year and a half and it sounds much more engaging, quiet, pure, and detailed than it used to.  But a little while after making any of these changes, I forget what it sounded like before!  For a perfectionist hobby like this, what a curse!  Always chasing that next noticeable sonic improvement, despite the diminishing returns...  

Who else struggles with this?