Sci-Fy/ and other genre: Books with a ruthless, hardened and strong female protagonist/ character

Ok, so I've just finished playing the Mass Effect Trilogy (again), but this time I finally played a mostly renegade female Commander Shepard and I gotta say, it was a way better experience than all those times I've played it before. The reason for this was of course the voice acting but also the way it feels to have a well-written, hardened and ruthless female protagonist. The last time I've seen something similar to this was in a Manga: "Ghost In The Shell: Standalone Complex".

Ok, so basically I'm looking for a hardened, strong and ruthless female protagonist/character. A person who Is willing to sacrifice everything to reach her goals. Obviously it would be perfect if she was a career soldier like shepard. I don't want an evil character, she should still be capable of compassion or romance. It would be perfect if the book would go down the road of exploring and changing the heart/soul of the protagonist, perhaps through a romance or friendship, but without sacrificing the characters integrity. A good example for this is the 2007 Hitman movie. I'd prefer a book which fits into the Sci-Fi genre, but if you have any good suggestions that don't, please, fire away!

Mass Effect is probably the best experience I will ever have with a character like that and the description of what I'm searching for is pretty detailed. So if you know a book where the protagonist doesn't quite fit that description but you still think it would be enjoyable enough for me to read I would appreciate it if you could post it aswell.

An example of what I'm not looking for: Ishtar's blade by Lisa Blackwood. https://www.amazon.com/Ishtars-Blade-Lisa-Blackwood-ebook/dp/B01C6X68MC

The protagonist in that book seems to be exactly what I want if you take a quick glance at the cover and the text. But as as soon as you keep reading past the first few chapters you realize she is deeply insecure, even submissive. I am aware this book is quite cheap and I didn't expect much from it. However, it is a perfect example of how a strong female character shouldn't be done.