Watch the games, but watch them a little differently: get ready to cheer for young guys stepping up in big moments, making plays you didn't think they were capable of, and pulling off team wins against the odds. In fact, make "against the odds" wins your new measure of success.
When I started watching Celtics games with my dad, Walter McCarty was my favorite player (because of how much Tommy loved him). A Celtics vs. Pacers game was to me then what games against Miami are now. The miracle game against NJ in the 2002 playoffs was the most exciting thing I'd ever seen. There wasn't a whole lot to cheer for over the next few years, but I still loved our team. We have some real dud players, but we also had guy who played hard and wanted to win despite the team's limitations.
You just have to embrace the lower-tier rivalries, get exciting about the development of young players, and cheer your heart out for well-executed plays. I love this team and will always find a reason to get excited about watching them play.