I really liked Nela - she reminded me of a lot of my friends, and, well, myself as well. It was pretty shocking to see what happened to her in the end. She didn't seem like the sort of person who would become (for all intents and purposes) a suicide bomber.
Theories on what prompted this/what it means??
The only things I can really think of is that we know she was getting into hot water from some other Manifesto/Marxist members for not getting involved enough, or being willing to take radical action. I wonder if she was trying to prove some sort of point to them - but still, it seems out of character. Or maybe someone had something on her that prompted such drastic action.
The only other thought I have is that the bomb wasn't really a bomb, but some sort of teleportation device, and Nela is now happily joining the rebels in Marcuria. But that is a bit more of a crack theory than anything...