Explain This...

I just played a game online for the first time, and the opponent didn't touch his controller at all, so basically I was playing against nobody, every time I tried to tackle him my player would miss the ball and foul the player resulting in numerous bookings and fouls also, when their GK took a goal kick even though nobody from his team pressed anything his players still won the ball by controlling the ball out of the air, even though I pressed header? Shouldn't my player be winning the ball?

Why is the game harder to play when the user doesn't even play the game!?