Sure, in idealistic romance world, yes. But in real life? I don't want to be that dependent on a person. I mean, if we naturally grow that close, and we are that intertwined (as if I have that level of trust for anybody), then that would just be... fact. I don't think my attitude would really be positive or negative about it. We'd be a unit. That would be fine.
Now, to psychoanalyze a bit, I may be downplaying how much I care about this precisely because it is something that I want so intensely (Enneagram 4 sx/so), but I think it's not something I'd ever strive for or expect in a relationship (except subconsciously). I do suspect that it would be a perennial source of a kind of background radiation of comfort, though, if I were so close to somebody else that we sort of merge or combine (anybody, really; our paradigm for closeness is the romantic relationship, but I don't care what form the intimacy takes; although I do admit that sexual intimacy, as an external manifestation, makes it a lot easier to achieve psychological intimacy, intimacy of the spirit-mind-nous-psyche). But then that person (or I) would be sure to die (and which one died depends on which one is the protagonist of the story; which one is Augustine, Tennyson, Achilles, Montaigne, Orpheus).