A friend of mine is married to an old school friend, and they have two small children. She discovered he was having an affair two years ago, and his refusal to acknowledge the hurt and betrayal of this has led to the permanent breakup of the relationship. He is now barely supporting her, although he earns much more. He won’t do school runs as his job is “too important”.

He’s now living with his parents and has little contact with friends, hardly any of whom know what caused the split. He is making her move out of the apartment they shared, and forbidding her new partner having contact with the children. The question is, should I be helping her find a pitbull of a lawyer, or is it a) advisable and b) morally OK for me to talk to him in the hope of making him realise what his awful behaviour is doing? I am afraid he might take it out on her if I approach him, but I can’t help remember what a reasonable and lovely person he was previously. Part of me hopes he might wake up. Am I wasting my time?

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