Borderlands 2 boss fights: is it just me, or are a lot of the story bosses extremely hard?

I've been playing through the franchise in prep for Borderlands 3, and Pre-Sequel and Borderlands 1 weren't pulling your hair or rage quiting hard like Borderlands 2. I'm on the final boss of the Commander Lilith dlc and I can't get it to half heath! I've had a lot of pulling your hair out moments with the bosses, but I was always able to find some trick to them after a while of figuring it out. That said, this boss basically kills you in two hits and your done. I don't know if people have any tips or what to do, but help would be appreciated.