First of all, I want to say that i don't believe in ever "completing the work" - i believe personal growth is an ongoing, lifelong process.

I mostly use my behavior as an indicator of progress, because emotions are more ... open to interpretation, so to speak. Say I do something that I used to be afraid to do. Or I manage to do something in a healthier way than I used to, because now I think and feel differently.

Another indicator is my perception. There are things I used to tolerate years ago which now I don't accept. Now I see much more clearly when my personal boundaries are being intruded upon, than I used to years ago.

But basically all of the above can be described simply as being different (in a good way). I think that is progress.