You can gather your souls back together by doing a specific deep remorse ritual but somehow it may destroy and kill you. It will be excruciatingly painful. This process will force you to fully regret and feel exactly for what you have done. It is believed that you, most likely, will be unsuccessful to undo your Horcrux but there is no way to put yourself back together other than this painful and horrible deep remorse ritual.

Horcruxes made from inanimate objects are extremely difficult to destroy. They cannot be destroyed by conventional means such as smashing, breaking or burning. To be destroyed, a Horcrux must suffer damage so severe that repair through magical means would be impossible. Very few magical objects or spells are powerful enough to achieve this. The person that tried to destroy it might suffer from a repellent curse exerted by the power of a Horcrux itself. Once a Horcrux is irreparably damaged, the fragment of soul within it is destroyed once and for all.