She has your spouse's heart. Literally. Your spouse had been on the organ donor list. One moment, there was life, laughter, and a future; the next, it was all gone. Since then, your presence has lingered in the rhythm of the borrowed heartbeat. And now, she has decided to find you.
Ultimately, doubt gave way to need. She found you, saw how you existed in her heart, and whispered, "I've seen you before...you've always been in the heart I borrowed."