Donna can finish a total of 8 x 5 = <<8*5=40>>40 episodes during the weekdays.
Meanwhile, she can finish 8 x 3 = <<8*3=24>>24 episodes each day during the weekend.
The total number of episodes she can watch every weekend is 24 x 2 = <<24*2=48>>48
Therefore, Donna can watch 40 + 48 = <<40+48=88>>88 episodes every week.
#### 88