Alves was left with a bittersweet feeling after Juventus advanced to the semi-finals 3-0 on aggregate following Wednesday's goalless draw.
The Italian visitors held firm at Camp Nou midweek, neutralising Barca trio Lionel Messi, Luis Suarez and Neymar.
Alves was seen comforting a tearful Neymar post-match and the Brazilian admitted it was painful inflicting misery on Barca, where he won six LaLiga titles and three Champions League crowns among others before leaving last season.
"It's different. So far the feeling is a bit strange, bittersweet, by the fact that there have been so many things lived here and then you have to come back as an adversary," Alves said.
"I had already passed this stage of having to come to face Barcelona, but unfortunately life forced me to come back here on this way.
"I had already spoken before that I would not want to face them, not by fearing them, but by the fact that I did not want to feel that feeling that I ended up feeling, but I believe we have to leave the sentimental part aside when you are wearing other colours and when you live your profession with as much intensity as I live."
Of the result, Alves continued: "Neither in their worst dreams [for Barcelona] or in my best dreams I did imagine that this could happen. But this is what happens when you compete a competition of a such high level, where you have to face the best and today we had the happiness of overcoming them.
"I think we made a great knockout. Not conceding a goal against this trio [MSN], against this team is very difficult and I believe this is our great merit. For all the effort we made, the clever way to compete against this great team I'm pleased to be in the draw on Friday."