So, I've read ultimatums are beta and I agree. I've also read its OK to lay down the law if shit gets shady.

Like if a LTR suddenly flakes on dates. I feel like the typical trp response of withdrawing attention / plate kind of allows her to 'get away' with this behavior or think she can. In such an established relationship id rather lay down the law and let her know it wont happen again.

Recently, my ltr was exhibiting really shady behavior and after flaking I called and told her to come over NOW to explain or else I was done as her recent behavior is disrespecful. Turns out she had good excuses.. I cant seem to think it came off as weak and made her vagina dry up.

Are ultimatums like that ever OK? How do you establish absolute boundaries without coming off fearful/weak?