Honestly, you've been with him for 10 years, and unless you haven't really brought this up before (which you say you have) I doubt he'll change without you actually putting pressure on him to change, and even then there's a big possibility that he'll keep up with these shenanigans..
Your boyfriend sounds very immature. He's 32, and it's kind of unacceptable at that point. It's kind of cute when a teenager is like "I'm gonna be a rockstar" but that quickly becomes old after they turn 18. It's fine to have a dream, but not one single artist has ever just had fame and fortune fall into their lap or handed to them for a minimal amount of work. It doesn't even sound as if he puts a lot of effort into his music career. It sounds as if he'd waiting for "the right person" to stumble into his life, and then they will make him famous.
Either way, I just think you have some thinking to do. Are you OK supporting this man for an unforseeable amount of time in the hopes that he'll become a rockstar? Is it even realistic based on his talent that this will ever happen? Also, think realistically how a life with him would be. You don't go into much detail about how he is in regards to other things, like if he helps with chores and all of that. If you want kids, what kind of a father do you realistically think he'll be? And I mean based off of past and present behaviour, not through the lense of someone who loves him. If you feel like you still think this relationship could be saved, I think it's time to pull out one hell of an ultimatum, and they're never fun really, but there's a time and a place. So, you're going to have to sit him down, and tell him that either he seriously grows up and starts living in the real world, and gets himself a job that earns him enough money to help pay for half of all of your expenses, or you leave. The thing is you'll have to follow through. Once you make an ultimatum you cannot back down. It'll suck really bad if he doesn't change, and it'll hurt. But in the end it'll show you that he doesn't value you enough to put even an ounce of effort into your relationship.
The only positive thing in that situation is that hopefully he'll be forced to get one of those dreaded jobs since you won't be there to pick up his slack. Maybe it'll even make him realize what an idiot he's been and meybe he'll change and become a better person for the next woman he meets, and that's always a good thing, even if it's still sad.
But hopefully it'll really light a fire under his ass. Either way, you're worth more than spending your life being less than happy, so I say go for it.