"We're very open with each other, but-"

Something I've consistently noticed about male-partnered women is how often their venting includes some variation of them making a disclaimer about how mutually "open" they and their male partner are with disclosing things to one another in the relationship, or how "open" their male partner is with them, only to be followed by a vent about how "off" their male partner is behaving, discovering an ongoing hidden porn addiction, sudden noticeable changes in habits, etc.

"My partner and I are very open with each other, but-"

"He's very open with me about what he watches and who he follows online, but-"

"We tell each other everything, and he's already told me what kind of porn he looks at, but-"

"We've always been open with one another, but something feels off and-"

Or in some cases, a woman will voice concerns to other women about her male partner, but when other women highlight her suspicions, she suddenly tries to backpeddal and downplay it with something like, "we're very open with each other, so I doubt he's really hiding something bad!" as if men don't lie by omission, or won't selectively tell one truth to obscure the fact they're hiding another far worse secret.

(I don't really have a specific story attached or anything, just something I've noticed in general).