I just watched the documentary he's in, good stuff
Be honest about what you want, what ideas you have. Let him mullet over. vice versa for any interests he'd like you to participate in. It may take some prodding to snap 'em out of the bubble. For the introverted among us who need to take it slow (while having plenty of time and space), perhaps plan something together in the house within a general time frame (no particular deadline so to ease the pressure of rising to the occasion when they're less than ready) where it's still within their comfort zone. And venture out from there. Baby steps.
If you all live together, I would think you spend quality time talking to him (and listening) on a usual basis. Learning the context of his moodiness. keyword listening.
“Some people say solitude is their biggest fantasy; some say it’s their biggest fear. But when I ask why, they all give the same reason: hearing themselves think.”
The good threads are tucked in between, just gotta reach down.
From experience,

Air: Aquarius (interesting conversations that jump around. I can deal with the detachment if I leave out certain feelings and thoughts that kill the flow. Purely intellectual)

Earth: Capricorn (I can appreciate their guardedness before you prove your worth to them)

Fire: They'd all have to be friends, nothing more. The selfishness would get to me.

Water: Scorpio or an outgoing Cancer. For a lot of fish I come across, it's pleasant and fun but it doesn't really go anywhere.
As flashy and open as he could be, there's that part that wanted privacy, and well, that just doesn't happen once you hit it big. I felt for him, the guy carried a great weight.

4 days
No shenananigans. Supermoon is watching.
Sewer Shark for Sega CD. Those cutscenes are fresh in my mind still. My CD was damaged and it would freeze whenever I came near the last level. It was torture
Sun square Uranus = badass
Venus trine Uranus = romantic badass
Some Cap/Saturn people just don't want to be pressured or rushed. The relationship needs to be grounded in some sort of structure and that's too predictable and boring for some. You seem to want a quicker pace than her. Also factor in any neurotic tendencies (esp. related to money, self-worth) that keep them from opening up easily. If you're patient now, expect to be patient with them long term. It really has to be in your personality naturally, not a one time thing.

Good luck with the fish, maybe she has some fire placements that complement yours
Good things come to those who wait. Gotta work hard to be permitted into a cap's sex dungeon
Part of the meaning is how they flow with a melody