[Rant] Build up the center, they say!

In most recent games, the opponent just attacked aggressively in the first 5 moves and I am somehow not able to defend correctly.

Also, the opponent is usually not playing "stockfish moves", so I have the feeling they wouldn't stand a chance moving that early that aggressively if their opponent wasn't me.

(10+0 rapid at >900, <1000 ELO)