Paul Pierce and Celtics fans became family during his time in Boston.Last night as rumors of the trade that sent Paul Pierce and Kevin Garnett to Brooklyn broke, I had kind of a selfish thought: “What am I going to do about my wedding cake topper?”I’m getting married in about four weeks, and my fiancee — a very understanding person — ordered me a Paul Pierce cake topper, knowing that to keep me interested in the wedding proceedings, she needed to cater to my basketball needs. Now I’m debating whether or not I should keep the topper and risk the pangs at my reception, especially if someone who doesn’t watch sports as much comes up to me and asks “Hey, didn’t he get traded?” Violence might ensue.Sports get tied up in our lives in weird ways. If it wasn’t for basketball, I probably wouldn’t have a Twitter account. If I didn’t have a Twitter, there would be at least 20 people who I interact with on a regular basis (and many, many more who I interact with less frequently) who I never would have met. Sports brought us together. It creates families.But it’s not just fellow sports fans. We end up adopting the players into our families as well, even if sometimes that relationship is a little bit one-sided. You want to know why it hurt Cleveland so badly when LeBron James left? It was because he was rejecting their family. He told them, in essence, their family wasn’t good enough.But sometimes, the relationship isn’t one-sided. Sometimes, the player adopts the fans into his family as well, if not individually, then as a collective. The fans support and uplift a player like a family would, supporting and cheering for him unconditionally while chiding his mistakes. In return, the player loves a city. It becomes symbiotic, and at its best (Duncan in San Antonio, Dirk in Dallas, and — of course — Pierce in Boston), it becomes the kind of relationship where a fan base actually appreciates the player’s importance to the city more than anything. More than wins, more than losses, more than future assets.Paul Pierce was that kind of player. There’s a reason no one can quite process the prospect of seeing him in another uniform — he started here, and it was pretty widely assumed that he would finish here after he inked his last deal. Many fans (and “fans” is the important distinction, since it’s GM Danny Ainge’s job to make the franchise better emotionlessly) cared more about Pierce than the Celtics in a lot of ways, wanting him to retire with the team because…well…he’s family.So really, no one is wrong here. The fans should be engaged with and supportive of their superstars. The franchise should be looking to improve whenever possible. But sometimes, those visions clash, and when they do, it can make for an extremely bittersweet goodbye.Boston fans have a tendency to romanticize players’ connections to the city, in part because of the long history of excellence within the franchise. But it’s not exaggerating to say Paul Pierce is one of the greatest Celtics in the team’s history. Since the postseason, my dad has been saying that he wanted the Celtics to run it back again. I’ll admit: I disagreed with him, because I want the team to be in a good place for the future, and I know that the quickest way to do that is to gather trade assets and get bad for the 2014 draft. But the more I thought about it, the more I realized that blowing things up meant saying goodbye to family — family, what’s more, with whom we have had an unbelievable stretch of years. My dad was right. How do you say goodbye to that?I know, intellectually, that the Celtics did extremely will in this trade. But family isn’t about being intellectual, and this trade is about family. How are we supposed to support a draft pick, at least right now? A draft pick is an asset, not a player. Hopefully, someday, that pick will become a player, and if that player becomes a Celtic (not a “Celtics player,” mind you, but a “Celtic” like Pierce), then he will join the family as well. It’s happened before. But that doesn’t make it any easier right now.Fifteen years ago on draft night, my dad and I watched disbelieving as Pierce’s name slipped further and further down the draft chart, and we yelled, high-fived and celebrated when the Mavericks took Dirk Nowitzki, acting like we had just won a championship.And, as it turned out, we had.Thanks for everything, Paul. You will be sorely missed.Follow Tom on Twitter: @Tom_NBA, where he will be sad for days.