What do you mean? Magi Tower crisis was resolved, the werewolf thing was resolved, one way or another, Blight was averted (for a time being... but this generation is probably safe) and Farelden Civil War was ended and the new King/Queen was elected.
How were you used as a pawn by Flemeth? She didn't really use you, unless you agreed to Dark Ritual - and you can avoid that.
Before Ostagar, there was (1) no crisis at the mage tower, (2) a stable king in Orzammar, (3) a Dalish clan unthreatened by werewolves, (4) a kind of incompetent Theirin ruling Ferelden alongside Anora, and (5) Arl Eamon raised Connor along with his wife Isolde.
By the end of DA:O, there was (1) no crisis at the mage tower, (2) a stable king in Orzammar who might have the anvil of the void and expand his people's lands, (3) a potentially dead Dalish clan or a cured werewolf clan, so that's a new thing; (4) a kind of incompetent Theiren ruling ruling alone and/or with Anora, or Anora ruling alone, and (5) Arl Eamon was alive, who either had a new daughter with Isolde or sent their kid off to the Circle.
In either case, the changes were minor. We don't learn anything about the blight, and we don't really stop it - we just kill off an archdemon, which is the same stopgap it's been for centuries.
And for Flemeth, she's using you as a pawn regardless of whether or not you go along - and telling her off just means you're either consigning yourself or Alistair/Loghain to death.