Completely unrealistic, laughable.
The character, a lawyer (you’d think she’d have some sense) survives a plane crash, manages to keep a single fire going for days in the wilderness, eats poisonous berries and throws them up, digs a hole deep enough for a fully grown dead man’s burial, gets lost in a Forrest, doesn’t eat, falls down a sink hole, gets her lower body trapped under a massive boulder which she miraculously frees herself from, then falls from a cliff - survives that and walks away from it, drifts down a river with currents, water rapids and waterfalls holding onto some wood. Impressive…. let’s add that the whole time she lives off other edible berries and rain water, is mobile, hallucinates the whole time, in almost clean clothes with tidy hair and clean skin, swearing every second breath and the best part is, she does all this while pregnant… oh yeh and I forgot, at the end she dies but someone gives her CPR and guess what…. She comes back to life :)