I have many times struggled with this as in the past I always tried to see the good in people but ended getting hurt and even when getting hurt still tried to see some good. I see it as in the bible it says about having the innocents of a child I believe what one part of that involves meet people with a friendly attitude and believing that there is good in everyone if that makes sense.
I do believe everyone has good in them the thing u need to work out is how much bad is in them that pushes the good down.
There is onlyone Good and that is God my Father is what Jesus said, and in the new Testament scripture it we all have sinned and no one is good.
The only Good I have is Father the Father of Christ and Irecieved this by belief in the Son Christ Jesus and not all that say they know him do!!!!!! but if we are harmed why don't we take it and learn from it andnot harden our hearts as it is obvious that others have and what they did was and is meant to harden our hearts. To keep us from the truth. Now have you ever had or been an enemy of another? And when you were an enemy of another and you knew they knew what you did to them and they treated you with kindness held no record of the wrong you did or have done. How did or would this cause you to feel?
Now do we all see the scarifice of Christ and are we going to respond with thankfulness seeking the new life that is also Found in Christ after we settle the issue that we are forgiven and thus can recieve the love of God installed in us and do the same to our enemies bringing in the sheep, where God the Father gets the credit for this for it is his love that is expressed through us, we are just partakers in this type of love that is unnnatural to flesh, This love is 1 cor. 13.