Presently, they were enshrouded in a fog of unfathomable mystery. Only two choices presented themselves to Sheyan - To advance or retreat. If they retreated, they would have to once again cross over that strange lake, the desolate forest and the icy cold winter valleys. Lastly, they had to face the risk of capture by Uruk-hais..... These matters have already been witnessed personally by them. They knew of the terror and dread it held, thus Sheyan wasn't willing to experience it again.
Hence without much deliberation, they affirmed their decision to carry on proceeding forward. No matter what danger lay in store for them, as long as they could drag on further an additional second, it would be worth it.