Think of the requirements to obtain salvation like a recipe. If you don't include the right ingredients you cannot achieve the desired result. Ego can result in sin but sin is not limited to just ego and encompasses anything that breaks God's laws. When we choose to bear the weight of our own sins by rejecting the free give of forgiveness being offered by Jesus then we make a mortal mistake from which we can never escape the consequences thereof. Only by confessing your sins directly to Jesus can you obtain forgiveness from your violations of God's laws. When you wrong another person(s) and confess your wrong to them and ask for forgiveness from that individual or individuals that is morally correct but it doesn't obtain God's forgiveness.
You can bang away on me all day long over this truth but in the end when you draw your last breath in this life you cannot say that someone didn't try to tell you the truth. 1 John 1:9 says to confess your sins to Jesus and he will forgive you of them. John 1:1 says that Jesus is God and 1 John 4:1-2 states that only a Christian has the ability to confess that Jesus is God in the flesh which is the hallmark of a genuine Christian. People can claim to be Christians all day long but if they cannot confess this truth then the spirit of God is not in them as is described in Matthew 25:1-13. People who depend on religion to save them have made a grave mistake as Christianity and religion are not the same thing which Jesus himself demonstrated many times as he stood in the way of organized religion and their message of hatred.