I have a co-worker who is mentally ill. Now, before I knew they were ill, I would get upset at their behavior  towards me. Frankly, they're rude. But, just today, The Lord opened the eyes of my understanding and showed me they actually do suffer from a mental illness.  This led to this thought -

Everyone on earth who is not Born-again and filled with the Holy Spirit is mentally ill, or, let's say spiritually ill. Either way - they're sick. Knowing this, knowing hate, lust, greed, pride - all of it is a result of a sick soul - makes their behavior much more bearable  - like Jesus did when they were committing suicide by crucifying Him and He said "Father forgive them! For they know not what they do!" Can you say this as they're crucifying you? Can you choose not to retaliate or get bitter but rather pray for them?

I once worked in a mental hospital (my wife thinks I was a patient there, lol). I worked closely with the patients - the point is, when one is surrounded by mentally ill people,  your heart breaks with compassion for them. You don't get angry or upset at their behavior or words, rather, you're patient and kind and long-buffering  - you forgive them and pray for them, knowing how ill they are. Would you get angry at a cancer patient who doesn't have long to live? Who doesn't have the strength to stand and walk with you? Or to clean up their own messes they make? Then neither should you get angry with the sick, lost souls you meet who hate or despise or ignore you. This is how we should treat everyone who sins against us - with love, forgiveness and compassion  - reminding ourselves they're sick.

Jesus is their cure - he's only a heartbeat away - one prayer can free them. The cure for their sickness,  their sin, soulish and spiritual is God's love expressed through us and his word spoken by us. When Paul heard Stephen forgive those who were stoning him - it pricked his heart and cut him to his core. When they see us react to their hate with love - it will convict them to their core too - they may harden their hearts further but they may also soften their hearts, with God's mercy. As someone once said - don't be hurt by them - hurt for them. Or, put another way, don't let the wounds they inflict in your heart and soul cause you to wound them back.