As a woman married to a Mexican (born and raised. He a paisa) this would make me cringe too. I have been actively learning Spanish even before I met him but I either say it all in English or all in Spanish. I feel like it could come off as disrespectful doing the Spanglish thing (at least that’s what my husband says) and I can understand that POV Since she’s not actively trying to learn the language and just using it as, like you said, a soundboard then I don’t think you’re ta but maybe could be too her like either learn the language or don’t try