In D&C 136 we also read that the saints were promised they need not fear their enemies; that the Lord would "do (his) pleasure with them". This was also the case with the Israelites who crossed through the parted Red Sea that came crashing down over the Egyptians, their enemies, who were chasing after them. Each of these groups witnessed miracles along the way. The Lord promises, "marvel not at these things, for ye are not yet pure; ye can not yet bear my glory; but ye shall behold it if ye ae faithful in keeping all my words". He would show them his glory after the trial of their faith which, since they were tried from the beginning, I think he showed them bits of His glory along the way, helping them keep hope and faith. The Mississippi River even froze over for them to cross. This parallel to the children of Israel is a pretty clear one to me!
At the end of their journeys, it is true to say that both groups suffered immeasurably. Yet, for those who made it to the promised land, they could see the hand of the Lord in it. The Lord does keep his promises. In Exodus 13, Moses tells his people "remember this day, in which ye came out from Egypt, out of the house of bondage; for by the strength of the hand of the Lord brought you out from this place". The saints knew this was also true for them and they established a headquarters in Salt Lake.
It's incredible to study and compare these two groups of the Lord's faithful. Both suffered immeasurably but in the end were blessed immeasurably. We read account after account of these miracles in the lives of the saints who crossed west. The Lord keeps his promises.