Am I a bad girlfriend (I promised my boyfriend not to tell my parents but my mom ended up finding out and I couldn’t hide the truth on my face)?

So I promised my boyfriend last night that I wouldn’t tell my parents that he’s worried that his mom could possibly have dementia. And I was hesitant but because I wanted some advice I was talking to my mom about it but I didn’t tell her who it was. She ended up guessing that it was his mother and I didn’t know to hide it with my face so I was just like “damn I’m caught “ I haven’t told my father anything I just told him that he’s very sad and that he’s worried about one of his family’s member’s brain health. I just wanted some advice I have never seen my boyfriend so sad before. I’ve only told my mom and one of my friends and her anonymously that’s it Also would sex make him feel better?

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So my mom just said “ I know it’s his mom” and I gave it away with my face
Am I a bad girlfriend (I promised my boyfriend not to tell my parents but my mom ended up finding out and I couldn’t hide the truth on my face)?
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