The question of our conscious can have many answers. Is it all real or merely an illusion of our mind?

Maybe it's a question that don't need to be answered but instead accept that what we as an individual experiencing is real. Who am I to tell one that there's no God if that is what the person truly believes? In his mind there will be existing one and in mine there will be none. And even presuming that is a illusion of my own mind.

Our mind is a remarkable tool to make sense of whatever we experience, although it might not matter in the end. Even when we try to make sense of that we are nothing or as you said it, a drop in the ocean, then it's hard for our mind to truly accept that fact. Our life is short, live it!