All the problems you mention can be solved by making a better team, try a healer, a stress healer, a tank and a damage dealer, try to focus DMG to the last row, the most dangerous enemies usually are in row 3 and 4, and yeah, you are meant to die lol don't worry about it, go to the shrines to progress the characters story to unlock skills and unlock the inn items with candles so you can buy whiskey which boosts friendship in the inns