In what circumstances will the court award costs in a matrimonial matter?

In Wilson v. Wilson (1978), 1978 CanLII 1621 (ON SC), 21 O.R. (2d) 703, Griffiths J. at page 707 states: Notwithstanding that in matrimonial causes there is justification for the departure from the general rule that the costs should follow the cause, it is my view that there is still an obligation on the court under Rule 810 to exercise its discretion in each case and determine whether costs should be awarded in accordance with the particular circumstances of that case. It is wrong in my respectful opinion, to adopt as a settled practice that no costs should be awarded in matrimonial matters unless there were unusual circumstances dictating otherwise. Such a practice ignores the responsibilities of the court to exercise its discretion in each case.