The Tarot don't bring any bad luck.....it only so happen that you connect your misfortune to all the event, and superstition from your Grandmother.
Tarot in itself is a tool, that in the right hands can do much good, or if used by wrong people even damage.
It is not the card that do this, but the thoughts the Reader implant in the seeker.....just like your Grandmother implanted the curse idea in your head.
There is "thousand" and "thousand" that use Tarot card, either professional or to own use, it would be well known if Tarot had the ability to do curse by use
So you just find your Tarot ability back, and use it in the "service" of light, and you will do yourself good
Since this is not a reading request I move it to Tarot Forum.