Quote from Henri Nouwen

Pay attention to the people God puts in your path if you want to discern what God is up to in your life.

The most difficult or challenging people in your life will bring about God's purposes in your life if you have a good attitude towards them rather than resist or avoid them
They are God's tools to outwork His way in you.
So see them from God's perspective - to do something valuable in you no matter how difficult you find them to be