I read a graphic novel whilst working in a library that featured a female lead character, that lives on a space station of some kind that, after humans no longer live on Earth.
There was an older woman in it as well as her family member or guardian who I think was killed by some kind of gang.
Also there may have been either gang warfare or some kind or civil war that was breaking out on the space station, that led her to leave and join some kind or army or military group, where she was sent to fight on a planet that featured a void or portal that took the soldiers into the planet where time moved at a different rate, so a few hours or minutes at the base would mean a tour of several years had passed on the planet.
I read it in around 2010, but it may have come out before then. The cover was pink and white and the drawings were black and white.