<human>: For background, I'm 27 and happily married to my partner of 8 years. Neither of us is monogamous, both are polyamorous and that is a long term and stable pattern. 

We place no limits on how the other person conducts their other relationships. I'm the same with my other partners, be they more casual of more serious. 

This question is about one of the other relationships I have. 

I have only one cluster of things that would be viewed as hard limits, and I make sure this is known: disease risk disclosure. Explicitly this means let me know if you think you might have an STI, let me know if a recent partner returns a positive STI test, let me know if you start sleeping with someone new before you come near my genitals or I go near yours, or if you have unprotected contact with someone else's genitals, or they have unprotected contact with yours. 

I feel I'm pretty good at doing this for anyone I'm seeing, and I get very frequent STI tests (3 monthly) so it's not just words without substance. 

Basically, as good as the sex is with 21F I no longer believe her disclosures about the above. This is because she'll rationalise why things don't count, and is not forthcoming with disclosures. Like, I know she's seeing  other people, I know she's sexting them, and this is a non issue. In fact, I'd be amazed if she's not fucking them, which wouldn't be an issue, but its not what she's claiming. Given the fact that she's shown she isn't forthcoming with such disclosures before, I'm out. My question is do I tell her why?

Can you condense the text into a few key points?
<bot>: I'm getting out of a non exclusive relationship, do I tell her that it's because I don't trust her disclosures around relevant disease risks?