You’re not the guy that did the whole “Colombian women are snakes” thread are you? I don’t remember.
Who cares? Putting a tracking device on someone’s vehicle isn’t at all healthy.
If you were in a situation where there was possible litigation with fuckloads of money on the line or something, maybe I could see it. But for two random people in a relationship, that’s just weird.
And you were right - again, who cares? The trust there was already gone by that point. And that means one of three things: #1 - she’s acting in a way that betrays your trust & doesn’t realize it; #2 - she’s acting in a way that betrays your trust, you’ve told her about it, and she’s continuing to do it, anyway, or #3 - you have trust issues you need to deal with.
Unless it was a #1 situation, the only real solution is to just end things and move on - not put a tracking device on her car like some kinda stalker. That shit not only is weird AF, but makes you look bad.