Because you're looking for a week that starts on Monday instead of Sunday, you can't just group on the date field and display for every week.  So, I would try creating a formula that looks something like this:

 

If DayofWeek({table.date}, crMonday) > 1 then

  {table.date}-DayofWeek{table.date}, crMonday) + 1

else

  {table.date}

 

This looks at the day number in the week based on the week starting on Monday.  Group on this formula to group your data by week.

 

-Dell