If you're only looking short-term, then I have to say it's probably in his best interests to put his relationship with his family over his relationship with you... because his family will always be a part of his life. If he accused you of trying to make things too serious, then he's also aware of the short-term potential.. so why on earth would he put his partner's needs over his own desires? People are pretty selfish like that.

Don't get me wrong, it still sucks that he didn't consider YOUR time at all. That isn't fair of anyone.

Also... if I was to find someone's family dynamics to be not-suitable to myself.. I would have to seriously reconsider the relationship. People are veeerrrry unlikely to change their relationships with their family and any attempt to do so will likely end up with resentment. True, people need to learn and accommodate their partners. And that's a valid thing to point out. But if someone is pretty much totally enmeshed with their family? Chances are, they're not going to change.