I think you're right to give it time.

But if either side wants you to give evidence to a court, then I think you're under a public duty to attend. But make it clear that your evidence will not be one-sided; that you will tell the whole truth; and that you will contact your friend's wife to indicate that you will not be hosstile to her case and if there is anything she wants to ask you, you will assist in so far as you can (i.e. you'll give truthful, full and unbiased answers no matter who is asking). Your friend may not be so keen to call you as a witness if he knows you'll do this.

I don't envy your position. Divorce is so very sad, especially when it is one's good friends who decide to go down the road to ruin. Only the lawyers benefit (but thank God, I am one!!).

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JJ Rodger
2013 G350 Bluetec
1999 SL 500
1993 E300 diesel T
1990 190