I know a male EIE who met and married an LSI female who basically supported him. They seemed pretty happy together, until he cheated on her with his HS GF and let her find out about it.
Maybe he was testing her love, maybe he was bored and needed an Fe challenge, IDK, but she kicked him out of their house and said she's done with him. That was two years ago. He thinks he's getting back in. I know some LSIs, and I have serious doubts. I think he completely misjudged her.
You really should never, ever lie to an LSI. And cheating? Well, just don't do it.
For insight into a female LSI's character, watch the movie RAN. The female protagonist is LSI.
https://i.imgur.com/87jo7ix.jpg