After taking a couple of days to consider just what in the hell happened, here's a guide to how you currently feel vs. how you should probably feel.
Mad as hell
If you're mad as hell, the key is questioning just who you're mad at:
Are you mad at Berkman? Not so fast, my friend. He got $8 million to play on a team with Matt Holliday and Albert Pujols - one that is a playoff contender.
"I can understand why people would feel that way, but really I'm not motivated by revenge. I'm not looking to come back in here and do anybody any harm or any damage. I just feel like St. Louis has a good team. it's a good city to play baseball in. I like the opportunity."
Are you mad at Ed Wade? If this is the overwhelming emotion you feel, it's probably the most appropriate, given the circumstances.
"If it couldn't be here, this is the next place I wanted to be. The first call we made was to Houston. When that one didn't work out, the very next one was to St. Louis."
It was Ed Wade who told him, "No, thanks." When Wade made that decision, he knew Berkman wanted to play everyday, and play in the National League. Even though the Cardinals have to re-sign Pujols (and this is out-of-the-blue news), Wade should have considered the possibility Berkman would sign with the Cubs or Cardinals.
However, how did you feel when the Astros traded him? Relieved? Then what's the problem? He didn't (really) hit for the Yankees, why do you think he's going to hit for the Cardinals? If you thought his stock was falling, shouldn't it be a good thing that Berkman is going to a division rival, and playing a more demanding position?
Are you mad at the Cardinals? We're totally fine with that.
This is probably the dominant emotion. If you thought seeing Berkman in pinstripes was weird, wait until you see him with birds on the bat. If you're around the age of 30, then Berkman was a dominant part of your formative baseball years, and not the "I like baseball, and ice cream" years. The years where you first started paying attention to things like OBP, and SLG. The years where you felt like everyone in baseball owed you a handshake for 2004 and 2005. In your heart, you know that Berkman isn't the same player, but it kills you to think that he signed with the Cardinals out of spite, and he just might play a huge role in getting the Cardinals to the playoffs, and will play the Astros 18 times. So he's no longer out-of-sight out-of-mind. Sadness is a completely acceptable emotion.
This is a rather advanced emotion, similar to telling your friends that you like Animal Collective: it's impressive to say it, but deep down, you likely know that it's not true.
How you should treat Berkman upon his return in April
If you boo him, you're a jacknut. Granted, within a few minutes of the news, The Constable posted a rather hasty, violent tweet about Berkman. But that was a fit of passion (and he has been dealt with sternly). Do not hold it against Berkman. This isn't a Johnny Damon scenario, and while we can't remember a time that a significant Astro went to a division rival (Trever Miller doesn't count), it's just not the same. He wanted to come back, was rebuffed, and whether spite played into it or not, he gave the Astros the first crack at his services.
That said, if this stokes your hatred of the Cardinals and all they represent, so much the better.