Tarot cards aren't really all that expensive, I think that I would just buy a new deck. Just my opinion!
The proper way of disposing of Tarot Cards is to burn them or bury them, cloth and all.
If you consider them basically a tool and not to be revered or sacred,
thenthat would be your decision should you choose to do something else.
My question :
When you found them, where they covered in cloth, etc. ?
If so that to me would suggest that your husband considered them sacred.
If so then I would properly dispose of them, but again that is just my opinion.
If you get the feeling that using this particular deck isn't right for you, then I would
suggest properly disposing of it.
I hope this helps,
Thank you for sharing such a very private and personal part of yourself here with all of us.
Your comment about living with ghosts made me smile.
My grandfather always used to say not to fear the dead, but to fear the living.
As I grow older, I find that to be sound advice
I wish you and your family well along Life's Journey