You are awfully dang nice, Too Much. But that's OK - we can use a little bit more of that around here.
The thing is, a plot that requires a person to suddenly lose...well, everything - principles, ethics, judgment, loyalty, intelligence even - when she "falls in love"...the whole thing just annoys the HECK out of me, for a variety of reasons.
For one thing, it's lazy - it's a cliche, in fact. In this episode, they don't lead up to it so as to make it even plausible - they never do in TOS, which uses this plot device more than once. It just happens. She looks at him - the wonderful him - she lusts after him because even though he's an arrogant genocidal would-be dictator with megalomaniacal tendencies, apparently he's her dream man. (What the...?) Then he makes her feel like a real woman or something. And then...kaZAAAAAM! She's hooked.
For another, since it is usually a woman, it's also very often sexist. And in this case, it's doubly sexist since she does this awful thing and Kirk lets her get by with it. Because she did it "for love."
Yuck.
And even when it isn't sexist - equality does mean, after all, that women have a right to be stupid in addition to smart - it's still a cliche. If making a plot device plausible requires the audience - not the writers, but the audience - to create elaborate psychological justification out of almost nothing...this is not a good sign, plot-device-wise.
As an aside, of it's a plot device that even Shakespeare had problems with (and I'm thinking Troilus and Cressida here), that is also not a good sign.