Lodge the form pleading guilty with the court on Monday morning with a covering letter explaining the reason for your absence. Make sure you or your friend actually hands the letter in and explains it relates to a hearing that morning. In the pleading guilty form state that you admit the offence but were forgetful because of your mother's death.
State in the letter that if the court wish for you to attend you will be happy to do so on another date, then if the court wish for you to attend they will set down another date and advise you.
The penalty is likely to be penalty points and a fine provided you do not have lots of previous offences.