There's something that you and others really need to understand. This IS their life! This is their Mission! While you and I are most interested in hanging out with our spouses, our kids, our friends -- while we are focused on earning a living so we can put our kids through college or whatever, these people are totally focused on their Mission.
The committed Left can best be thought of like Terminators.
"Listen, and understand! That Terminator is out there! It can't be bargained with. It can't be reasoned with. It doesn't feel pity, or remorse, or fear. And it absolutely will not stop, ever, until you are dead." - - - - Kyle Reese
To a committed Leftist, his life has no meaning except to the extent that he advances the Mission of bringing the world under total socialist domination. They will, like William Ayers, devote DECADES of their lives to the purpose of getting power to implement the Plan.