Sounds like you have something really wonderful going for you there, something that has enriched your life, made everything better, all out of the desire to please this person. It sounds to me like you are pretty submissive, just think about how it makes you feel when you are this submissive to this person. If it enriches your life, and this person supports you, builds you up, and makes you better, and you do the same for them, I would say dont fight it, embrace it if it feels right. You seem to have a good pace going, just go with it, and see where it leads you, whether that be subtle submissiveness, or completely submitting to this person openly, just do whatever feels right for you.