I love conversations like this as well and I much more prefer them over casual smalltalk (which I am very bad at :D). The only one outside of the internet I share deep conversations with is my sister at the moment. Before I went to Sweden we didn't talk that much about stuff like that but after I came back and she told me for the first time that she has depressions as well and that she goes to a therapist now. That was when those conversations started and I guess it is very healing for both of us. Even though I never would have wanted it to start like that; I never wanted her to experience something similar to my depression :( but she is a very strong person so she will get through that as well.
Yes I've seen ''Into the wild'' a few times now and I absolutely love that movie. I can relate to this phrase a lot because although I enjoy my time when I am alone, when there is another person who can experience the same things as you and you can be happy ''together'' it is like the happiness is twice as strong. I can't find a better way to describe it but that's how it felt like in Sweden.
I guess in a relationship like you have it is normal and important to take a step back from your own dreams to don't ''destroy'' the dreams from your partner. But maybe you can find a compromise that makes both of you happy. Just because he doesn't want to do what you dream of doesn't mean you shouldn't do it either. You could go on a trip alone; I don't know how far away you live from California but I guess for starters you could go somewhere else instead and bring back memories and experiences that may change his opinion and make him more open to see all the good things that can come from an adventure like that :) .