There is a simple sign that you really need a person.

Close, understandable, important. He is his. And this is a rather strange sign. You are angry with this person. Get angry. Offended. He terribly annoys you sometimes. You can quarrel with this person or leave him. Not very far to go. Because after five minutes or more you are drawn back to him. Well, in an hour, or in a day if you don't live together. And you are worried: how is he there? Or is she okay? And the soul is out of place. And together you are so good that you can be silent and not talk about anything. And so everything is clear. And you can talk for hours; and you are not bored.