Sci Fi/ any other genre: Books with a ruthless and strong female protagonist.

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". It would be ideal if the character was a simple soldier using relatively traditional weapons, not magic, for example.

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. 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 poste 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.