Why is combat so unbalanced?

My dislike with the game is I’m about a hour into the game and I noticed that if you get into combat with more then 1 enemy you spend about 90% of your time dogging and blocking because all enemy’s will hit you at the same time plus if your in mid block and another one attacks from behind you eat that hit no avoiding that not to mention the amount of health you lose form a single hit in my opinion is brutal it leaves no room to recover from a mistake you made.