However, you make it sound like it's super difficult to disappear. It can be as simple as getting on a boat and sailing off into the night, or an airplane... no Hollywood plot necessary - no one would have any clue who was onboard, and depending on the destination, they may not care either.
Going on the lam for the rest of your life, with (or without?) your two young children, can't be a whole lot better than serving your white-collar time, can it? I mean, it's not like she's independently wealthy and can vanish to some tropical island.
Staying disappeared is much more difficult, particularly if you are interested in living even a moderately normal life.