It sends both because of the structure of your macro. You've got 4 IF/ELSE statements going on when at most, you should have 2 but could do it with 1.

Leave the cable box on, all your doing is turning off the front panel, not saving any real money. You should be using only the TV Power On variable as that's all you need. You want it to delay 8 seconds but you don't have an 8 second delay anywhere! You're setting the Variable TV Power 4 different times in this 1 macro.

IF Variable TV Power On = False
TV Power On
Delay 8 Seconds
TV HDMI 1
Set Variable TV Power = True
Jump Cable TV Page
Else
Jump Cable TV Page

If you're switching from a different activity and need the HDMI input on the TV to change if it's already on, just add that command to the ELSE section.