Lords of the Fallen developer Hexworks clearly thought you were all having too nice of a time, so the game's most recent patch has made a number of bosses tougher.
With a genre like soulslikes, you can test your game as much as you want, but you can't ever really be certain about how tough a boss should be until the game is in the player's hands. Lords of the Fallen has been out for almost a month now, and it has already received some tweaks, but its latest patch will definitely amp up the challenge a touch. For example, the Sanctified Huntress boss can now use her dash-teleport when you've cornered her against a wall, so that trick's down the gutter. Griefbound, alongside her minions, are also more aggressive now, meaning you'll probably need to be a bit more alert.
The notes for patch v1.1.282 also note that it has "increased the challenge for a boss at the bottom of a very dark place. That aberration born from love now has higher pacing and a bit more punch." Sounds like you'll need to go and see the specific changes for that one yourself. Bosses aren't the only thing that have changed during the patch, there are a huge range of other tweaks too, though not all of them have gone down well with players judging by the comments on a Reddit post detailing the notes.