If you have a friend who claims he wants out of a bad marriage, you must say nothing. That is a decision that belongs to your friend and to him alone.
If you advise him to go ahead, and he regrets his decision later, he will claim you encouraged him to leave. If you advise him to stay, and the situation deteriorates, he will say that he wished he had left when he wanted to, and not listened to your bad advice. You can’t win.
Unless your friend is in actual physical danger, it’s preferable to ask him to call you when he’s made definite plans, then leave him alone to consider the consequences of his action. If and when he does call, telling you that his decision is final and he’s packing his clothes, then you can spring into action.
If it’s practical, offer him a place to stay until he can make other arrangements. Whether or not he accepts, the greatest act of friendship you can provide for the next few weeks is a listening, sympathetic ear. He will want to rehash his marital problems over and over, as a kind of catharsis.
He may also be experiencing a grief process. When a marriage ends, it’s the death of a relationship. No matter who’s at fault, or what the problems were, both parties have failed to live up the high expectations everyone held for them at the time of their wedding. The emotions of sadness, disappointment, anger and self-doubt have to be worked through. It eases the process considerably to have a friend nearby acting as a sounding board.
You can aid best by active listening and offering sound advice, remembering that a marriage is a binding covenant, and if there is any hope at all that it can be saved, that hope should be encouraged. Offer to go with your friend to an initial counselling session. If an arbitrator is needed between the marriage partners, you may be able to fulfill that role. Perhaps the children need to be taxied back and forth for visits. A true friend will help out wherever he can.
If, on the other hand, if the situation seems hopeless, your friend will need your help to accept reality and move on. Take him out to dinner and a movie. Help him reconnect with past friends and acquaintances. Offer to see a lawyer with him to get the legal issues underway. Go apartment hunting together and help him find suitable accommodations and necessary furnishings. Do your best to help him focus on hope for the future rather than on depression about the past.
When a marriage breaks up, each partner goes from being half of a couple to being a single person again. Each one needs support, a good friend who will stand with them until they are strong enough to stand on their own once more. Being that friend is an honor, but it also requires time and effort.
However, until the person leaving the marriage makes the final decision to do so, on his own, without any interference or advice from anyone, even the best of friends should stand aside and wait patiently.