As for the OP, since you are a colleague and not her boss, why the fvck you care? You could have refused to jump in for her, although, she might have done the same for you, when you wanted a vacation. And you could have planned the work better in order to have the weekend for yourself. Are you angry at yourself for bad time management, or at her for bumming around at home?
That being said, if I was her boss, and somehow learned about her decision to sit out a major deadline, I would for sure remember that in case of future salary negotiation, promotion, or bonuses. It's her decision, but so would be mine to consider her attitude toward her colleagues and firm. Every decision has its consequences.