It is just a hunch, but I think when it was climbing last summer, then dipped back down to the $6000 level in mid-November, big money must have come in a purchase large amounts of Bitcoin. I say this because it has held $6000 so many times.
The longer the Bitcoin Price stays at $6000 or higher, the harder it will be to go below that price. Also the cost of producing 1 bitcoin is also putting a bottom to the price of Bitcoin.