Sure, they had been through the destruction of their society, but, they picked themselves up and got on with the business of living like real people would do.
In nuBSG, the fleet made it to Earth with many survivors. Everyone who was physically and emotionally able to survive did survive, though many gave their lives heroically, so I'm not seeing your point here.
Perhaps you mean that it was unrealistic that some of them had committed suicide? If so, I'll be sure to let the families of real-world suicide victims know that their loved ones didn't really kill themselves.