I’m reading this entire piece on two levels. There is the relationship of two people and the universal relationship we all have that I gather from this highlighted statement.
Live interaction isn’t necessary to love. But, our senses ie, sight, touch, smell, hearing and taste are an important part of connection. I think I can actively love anything I picture in my mind via my senses. I think the concept applies to memories of loved ones as well.
I’ll go out on a limb and say I think feeling alone or lonely are the illusion of wanting something or someone we already have.