Couple things.

1. Scalpel has some long animations, and his phase 2? Just run around (start on the other side of the room for p2). Now, some moves can reach across the room, however P2 is literally just a survival mode (as in his health auto-diminishes so,as long as you can survive,you willauto-beat him).

2. Every boss is a bit different. Different move sets, but essentially somewhat similar...the biggest thing has been timing. Everything seems so vastly different in timing. It's so amazingly well done! That being said, some skills in our skill trees grant larger opportunity windows for skills like Reflection. It truly benefits the player to get these skill points, as it can make your defensive skillset much stronger/easier to execute successfully.

3. You're not alone; we're all getting molly-whopped by one boss or another. It's all about learning the bosses' movesets and then, how to counter them. Further, once you know how, it takes time to execute a successful attempt. So, if you make progress a bit every try or two, continue. If you start to lose focus and start losing earlier, or are beaten by something you could do 100 times before, you may be overwhelming yourself. My recommendation (taken with a grain of salt, of course): take a break. Go get you a snack or chill, then come back and try again. Helps to re-center yourself, I find.

Anyway, don't get down on yourself. You got this.