Yup, been here. My DH wasn't in a band when we got together, but ended up in one that was always on the verge of being signed (and they really were, there isn't a label that they didn't play for). They had some really really good songs.
I ended up putting money into that band, getting further and further into the joint overdraft, but had no say so in it. He was only able to do it because i was supporting him.
He took a job that required him to work Saturdays and Sundays, even tho I asked him not to, and was at rehearsal every night.
I'd go to their gigs and be the loudest one cheering in the crowd, and he'd ignore me pretty much. If I didn't go to a gig, I'd be accused of not being supportive.
He was tired and grumpy from being at rehearsals every night, and wouldn't get involved in the running of the house. He used to snap if I asked him what we were going to have for dinner that week, like I was pestering him. The band was always fighting within itself too.
He used to say he was doing it for us, since he didn't have a degree or any kind of career in mind.
Our wedding was nearly called off due to all this sort of thing. I would not have had a child with him if he hadn't quit. It was bad enough looking after two dogs on my own! He is now training to be an optician, which sounds a bit of a depressing "given up the dream" choice but he is happy with his career.
It did come down to the band or me. It sounds mean to give an ultimatum, but being in a band like that makes you really selfish. You don't get a choice in the matter, the only choice you can make is to leave them. Since you have a baby, leaving him would be an absolute last resort. But he needs to understand that he's made a choice to have a baby with you, and that requires him to make some sacrifices now.
So no, YANBU, from someone who's been there.
The band has dis-banded . The lead singer presents a show on sky channel 180 these days, and he's pretty good at it!