It seems like plenty of great thinkers have arrived at the same paradoxical conclusion that the capacity to be alone is the capacity to love. I think this makes sense when you take a little time to analyze it: if you need the other person, you are turning the other person into a possession/resource. If you are “full” independently, then that turns love into a gift. You can grant the other absolute freedom because whether they stay or leave does not affect your core. I will not cite the exact hadith, but the Prophet made it clear that true riches is self-contentment. What you don’t receive from the other, the other cannot take. Two solitudes protect, touch and greet each other.