Song lyric: "But this half-pint imitation put me on the blink"

"Bewitched", sung by Ella Fitzgerald and others, begins:

After one whole quart of brandy
Like a daisy, I'm awake
With no Bromo-Seltzer handy
I don't even shake

Men are not a new sensation
I've done pretty well I think
But this half-pint imitation
Put me on the blink

I'm wild again, beguiled again
A simpering, whimpering child again
Bewitched, bothered and bewildered - am I

What does the "half-pint imitation" refer to? Surely she's not saying that her lover is a "half-pint imitation" of a man? That would not make sense, as she's so infatuated with him.

Solution 1:

"Half-pint" in this context means inferior or lightweight (in the sense of lacking gravitas). Meriam-Webster's secondary meaning is a "short, small or inconsequential person". It can also be used to refer to a kid.

"on the blink" means broken or not functioning (the origin of the phase is discussed at StackExchange here).

@HotLicks has hit it on the nose in her comment when she states: "this person, whom she presumably underestimated initially, has swept her off her feet."