I don’t understand swingers etc. It would hardly be standard porn if half way through a threesome I stop to take a kitchen knife to the other woman.

Same. I hear some people like it, but then you browse forums and see all the stories about how one partner wants to stop while the other doesn't. Swinging and open relationships are possible, but it has to be a VERY healthy relationship, and even then, it needs more maintenance.

What about your spouse , would be the same way as well?

For an open marriage to work, both partners have to be open to the idea of having other partners. It's not so much that the one partner is passing the other around. But I can see how you'd think that from the way they present around here.

Quite easy actually. You are blessed with a mind and a will. If, in your life, you're blessed with discernment as well then, forewarned is forearmed. That little alarm going off in your head rings for a reason. Why have someone in yer life who can't be trusted? Shit can 'em.