Hi there, We've had tarot cards in my family for generations.
The quick answer is No you don't have to be gifted the cards, If we all waited for cards to be gifted to us, we'd be waiting a very long time, lol.
The important thing is that the cards match your energy and work well for you, not where they came from.
Carry on handling these cards every day, the more you do this the more "friendly" the cards will feel for you.
Sleeping with them under your pillow was a great idea and shows good instincts. You could also try holding them in an appropriate incense smoke to help purify them.
When not using them, wrap them in silk. Don't keep them in their original box.
Most readers have several packs of cards, different types of cards work well for different problems/types of readings.
If this is something that you would like to seriously learn, I would advise that you buy a standard Rider Waite based card set. With the 22 major (Fool/Magician etc) and 56 standard minor arcana(Cups/Wands/Swords/Pentacles). There are lots of beautiful packs out there to choose from, Ciro Marchetti does some gorgeous ones.
The cards you have look nice(I googled them), but they do represent a very specific faery/wiccan path, so it is possible that they just are not compatible with you/your beliefs.
If you continue having problems with these cards, then stop using them for now, put them away until you become adept and can try to bend them to your will, or just cut your losses and decide that they're not a good match for you and pass them onto someone else who they may match with.