Thanks for sharing, LovingRadiance. How do you hold "a tight rein" on your partner?
One thing we did just do was add this to our list of relationship rules: "If another partner or potential partner causes significant discord in our relationship, defined by multiple arguments about the questionable motivations, possible manipulative behavior, or ethics of said person, that connection will be severed. NO outside person is allowed to persist in a connection with us once they start to come between us."
D doesn't like this rule and argued that it is unfair, because someone who is not actually bad news could still be vetoed under this rule, if his reaction to the person triggered me in some way. I told him I didn't care, that him accepting the rule was nonnegotiable. He signed the amended copy of it, but was not happy about it.
I hate conducting my relationships this way, with ultimatums about things that even I know are not fair, but I know that one more incident like we just had, will finish us.