Plants in pots too close together starve each other. Good relationships need a little room to breathe.

Closeness has an optimum rather than a maximum. Two people entirely wound around each other end up competing for the same limited attention, interests and identity, and the shortage reads as a problem with the relationship when it is really a problem with spacing. Space is not distance, it is what allows each person to keep growing.

Keep something that is yours alone, a friendship, a practice, an evening. Encourage the other person to do the same without reading it as a loss. Most of what people bring back into a relationship was grown somewhere the other person was not.