The negative and positive aspects of our present life are the product of the deeds we have committed in the past. No one else can save us. All phenomena are without self. If there is a personal self it must be a name, a body, or a mind. And once we are caught up in this duality we have attachment and aversion, from which all the defilements are created.
External objects are also devoid of self.
A table, for example, can be reduced to its component parts, the parts to wood, the wood to atoms and so on. In reality everything is free of self. Nirvana is peace. Nirvana is the true peace beyond sorrow. To reach nirvana we need to subdue the defilements and then eliminate them.