The ability to be alone is the ability to love. It may look paradoxical to you, but it's not. It is an existential truth: only those who can be alone are able to love, to share, to go into the deepest core of another human being—without possessing the other, without becoming dependent on the other, without reducing the other to a thing, and without becoming addicted to the other.
I always cheer up immensely if an attack is particularly wounding because I think, well, if they attack one personally, it means they have not a single political argument left.