Shoelaces are the poem's one big image, and it carries the whole relationship. Two laces twist around each other, hold tight, loosen, and get pulled back together. The speaker uses that picture to describe a love that feels permanent but isn't always smooth. Being close brings happiness, and the fear of separation is so strong that the couple can't even cry about it. Yet the poem admits they "often fall apart," only to be "criss-crossed" again, just as laces come undone and get retied.
The speaker seems devoted and a little vulnerable. Calling their own soul "wretched" suggests they find comfort in the other person's heartbeat, as if that steady rhythm soothes them. The partner, meanwhile, longs for their touch. The repeated opening and closing line makes the mood feel circular and settled. It's tender and dependent, with a quiet worry underneath, but the ending leans toward reassurance: they exist for each other.