I think if he is marriage that should end any questions regarding what could be. If he is approaching you it is inappropriate - friends or otherwise. You have to be the person acting responsibly if is not. it doesn't matter what he wants or acts like remaining friends is the only solution. To facilitate that choose any method you wish. No one is pushing him in your direction except him. He has an intention and he has the power to make or break this decision. Let him know that you are friends only. Let him know you want to keep it that way. Anything that happens isn't fate - it is his intention. I do question why you don't let anyone get close. You need a relationship that is healthy and strong. This isn't it.
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