My boyfriend works too much

I think my boyfriend works too much. He’s salary, so meaning he does not get paid overtime hours. He goes to work at 5am, and stays until 4pm or even longer. I don’t know how to talk to him about it, but I feel like he has this tendency that he just HAS to fix everything even if it’s not his job. It’s annoying sometimes because he’s hardly getting any sleep, he stresses about it, but still tries to do everything by himself. I honestly think people in his workplace are taking advantage of him already. He told me he likes it when people ask him stuff because it makes him feel smart, but then he complains about how his colleagues are so incompetent. It’s really getting on my nerves. His work gets in the way of our plans, too. He’ll be so immersed in doing something (that’s not even his job!!!) and will make me wait 2-3 hrs before he can come get me because he forgot, and this is after we already made plans. It’s really frustrating and hurtful sometimes. I’m not sure if this is immature of me because I know work is also important but there are times that it’s just too much. I guess this is just a rant, I apologize and thanks for reading. Writing this down made me feel a little bit better.