safeword ignored... twice... by someone we trusted

long time bull, weve played with him eight or nine times in melbourne. weve always used "red". he knows it he respects it weve used it twice before for stupid little things and he stopped immediately. last meet wife said red. he slowed but didnt stop. she said it again. he kissed her instead of stopping. she froze. i was there i was watching. i said RED loud and he finally got off her. he apologised after, said he didnt hear her the first two times because of the music. wife says she believes him. i dont. i havent slept properly since. how do you tell your wife the person she trusts didnt earn that trust without making her feel stupid for trusting him. 44 me 41 her swinging 6 years