Just throwing this out here but do you guys think that invisible string could be Taylor telling us her and Joe are married. Kind of like the invisible locket metaphor
People call getting married “tying the knot.” The whole song she’s talking about tying him to her with an invisible string. The invisible string could be that they don’t wear rings in public to protect their privacy. At the end of the song she says “one single thread of gold tied me to you.” Wedding rings are usually gold bands.
I think it could be about them getting married. I know there’s all the character arcs but she also talked about how she mixed her stories in with them. That’s just my thoughts