[gamedori]

Ultimatums are one of the best tools for people in terrible relationships to use:

"Give up the bottle, or I leave."

"Stop hitting the kids, or I call the cops."

(Other ultimatums, such as "Marry me or I kill the dog" are obviously abusive.)

In this case, the woman is forcing the man into a choice, but he still has a choice. "Show me that I'm not wasting my time or I leave" is in the grand scheme of things quite tame.

[krageon]

If you have to give ultimatums about abuse you should already have left.

[gumby]

That’s easy to say from the outside.

There are many reasons to call attention to things not working (e.g. the bottle example given above) and the ultimatum can be the last step. And when kids are involved (not in this case) it’s typically better for all concerned to have two parents if that’s possible. So you may hang in there longer than might look sensible from the outside.

[mikeash]

Having experienced the kid side of this both ways, let me say to any parents in this situation: if your marriage is shit, don’t “do it for the kids” because of some notion that two parents is better. Get that divorce! Your kids will be far better off with two sane single-parent households than one messed-up two-parent household. Neither is great but being the third wheel in a broken marriage is worse.

[zeveb]

> Your kids will be far better off with two sane single-parent households than one messed-up two-parent household.

Perhaps, maybe even probably — but what about two messed-up single-parent households?

[dsfyu404ed]

That sounds all fine and dandy until the custodial parent goes out and finds a spouse that creates the same problems all over again. Then you've got the same situation but with three stakeholders and one with a lot less interest in the kids' outcome.

[mikeash]

I am well aware. But saying is a bad situation because you might get into a bad situation again is not a good strategy, and the fix for that problem is to get out of that problematic marriage too.

[jacobush]

Should, yes, but with real people in real relationships it's rarely simple.

[narrator]

Threatening to leave being the only persuasive argument that works on your significant other is a good indicator you're dating someone with borderline personality disorder.

[gamedori]

Ordinary people occasionally need to be knocked back into seeing what they will lose if they keep up their present course of action. Life is full of temptations, most people are not very self reflective, and people naturally push boundaries.

In particular, textual flirting with the opposite sex is something that is easy to fall into, starting innocently and delivering a strong dopamine hit with each correspondence. The dopamine-addled S.O. can easily rationalize to themselves that they are just writing, that their privacy is suddenly Very Important, it's not cheating, and surely that's not innuendo! ("When we finally meet for coffee we'll just be friends.")

The well-delivered ultimatum, although blunt, makes the situation clear and leaves no room for rationalization: the emotions associated with the proto-affair are inappropriate to an exclusive relationship.

I've had to make this ultimatum twice. 50% of the time it has resulted in the recipient suddenly becoming self-aware and making an effort to change her behavior. As a result, I'm quite certain the current S.O. is not BPD.