Isn't closely following sports at all immature?
In my opinion, no. It's a hobby, and it's entertainment, which is a perfectly mature thing to enjoy.
What I think is unhealthy, and yes, immature, is getting so wrapped up in it personally that players become "divas" and "traitors" when they don't do what you want. I didn't mean it as a deep judgement on anyone personally. I'm sure there are plenty of otherwise reasonable folks upset. Just calling a spade a spade, again, IMO.
I wouldn't consider it immature to label players as "traitors" and "divas". Many of us are emotionally invested, but it's all within the context of the sports world. My personal life isn't affected. When fans use the terms "depressed", "hurt", and "offended", I think the majority of us are applying it within the sports world that we live in. The Celtics just happen to be a pro team that I'm extremely passionate about. I care a lot about their success and I'm glad that I do. More than anything else, sports is a nice release from some of the stress that we all face within our own lives.
I will most definitely admit that I'm upset about Ray going to Miami. Being 23 years old, the Big Three represented the very last group of players that I looked up to from my childhood. On top of that, the way this group came together forever changed the way I watch sports.
Grit, balls, determination, heart and many other traits have become so vital in regards to my level of emotional investment in a team. These same traits have made me despise many of the Red Sox players. I've never felt so disconnected from one of my favorite teams. They don't represent much of anything that I like.