I want to also add that there were many reasons leading for all this to happen in the first place.
Seems like Anne had been knitting her own fate since the moment she became Henry's lover. Why? Because she insisted in that she was going to give him that heir that was the primary reason why his marriage frustrations happened with Catherine.
Not only did she fail to produce that first heir, and then had three more miscarriaes 2 of whom were boys, but, in reality, she missed to take notes on her husband's quick run of affections for just about every woman.
Even while married to Anne Boleyn, Henry had affairs galore. He was not one to keep his eggs on one basket unless a woman made it challenging, which is what Anne did at first, and then, well, the challenge was over.
Furthermore, as her attempts to give birth to an heir failed, and his infidelity continued on the rise, came the case of the Suffolk set: A group of courtieres who hated Anne for her beligerant and elitist behavior, and wanted her gone from court.
Hence, the best thing to do was to start rumors about infidelities (which are automatically classified as treason and punishable by death), witchcraft (which came as a result of more rumours regarding one of Anne's miscarriages to be deformed, and her having supposedly a sixth finger), and incest, which would make it further more disgusting to the king, and more easy to get her out of court.
These, whether true or not, were mostly accusations coming from those Anne hating groups, and from the Jane Seymour set as well, (not Jane, but her family) who were as ambitious as the Howards in obtaining the goods of the King.
Hence, the three years of Anne were filled with conspiracy, lechery, treason, gossip, failure, frustration, and since the King will always be the King, he simply opted to get rid of her as his eyes were goggling over Jane Seymour for hopes of an heir again.