Play another instrument for a while. Eventually you will come back to the piano. Along with m1469's suggestion, I'd say improvise at the piano. Doesn't matter if you don't know how, or if you think it sounds bad. Play anyway.
Hi Nightymelon,some ideas:1) Think why do you like to play the piano and what does it give to you. Go into the feeling that you already can do it. If you imagine the feeling that you could have while being able to do something or play a piece you really like, it can give motivation. Then you can direct the motivation into practicing.2) Listen to your favourite pieces.3) Think about positve events that have occurred during your piano-life.4) Listen to great pianists and child prodgies.5) Do something new, get some new ideas and information and use it practically in playing the piano. You can discover something that could surprise you and give you a push.These are some things that help me. Maybe they can help you too best wishes,Jaak
Taking a break isn't a bad idea in my opinion. Don't even worry about not playing. Come back when you feel like playing again and just passionately play something you enjoy. All work and no play makes Jack a dull boy.
I wish I could, but I'm not so sure how to improvise on the piano. It seems like a good idea, so I will probably look it up on Youtube to see how it works.