Seems that I heard early on that this song is the one that most addresses the band's breakup specifically.
I'm married to a recovered alcoholic. I could write a book on how Full Circle describes our life, too. Here is one point I can elaborate on for you.
"You cover yourself, you cover your skin
You cover yourself, like you cover your sin"
One of the most hurtful things for me was discovering that some of my own best friends would walk away from me because of my husband. When they found out that he was actually in a rehab place for several weeks, they never called and walked out of my life (and have never been back). I have never been hurt like that in my whole life. One week, we were best friends, and the next week, they were nowhere to be found. That is why this phrase really stings me... because it reminds me of how they "covered" themselves to not be a part of what I was going through when I needed them the most. Brought me to tears the first time I listened to this song, too. It's still hurts, I guess. I believe it's this kind of deep hurt and betrayal from people that supposedly love you that Stapp is trying to convey. It is an awful, awful thing.
Good luck on the project.