If in Scotland then no. It is not matrimonial property even though they are still married. All property acquired by them after the date of separation is individually owned. In addition, even if they had never separated and were living happily together it still would be owned solely by your blokes friend. Inheritance property is not matrimonial property. However the court would give regard to the resources of both parties. So if X inherits 1m and owns a share of the matrimonial home with Y who is in hardship, the court may give Y 100% of the home they own.