A lot of people dedicate their lives to a cause, and several of those causes are dangerous. Pretty much everybody who lives on the Blightborder has to do so with the threat of the Shadow at their doorstep and Trolloc raids killing them at any moment (or worse, getting them alive). People who join any army live with the risk of death, especially in troubled times like these.

Moiraine's sacrifice of 'her lifetime' to her cause is not much of a sacrifice, every one of those people I've mentioned has done the same, and many more. Heck, at least she chose to follow that cause, which is something that can't be said for people born on the Blightborder, or the three ta'veren, who had their lives thrust into a cause they did not desire, but decided to pursue anyway because they had to. That is sacrifice - they lost the life they wanted for one that was needed.