Do you think it's bad that I've been taking my husband's debit card and using it?
Have you been taking it without his permission or does he know about it?
No he doesn't know about it.
It's wrong to take something that's not yours and use it. You should not use your husband's debit card without his permission as it's a betrayal of his trust.
We share everything, I don't need to tell him what I'm doing.
Even though he's your husband, if that debit card is linked to his own account and not a shared account it's wrong to use the card. Talk to him and see if he's okay with you using the debit card, don't just use it without telling him.