If you use Alt-f4, you will probably also soon lose interest in your Ironman campaign. You know you cheated and you can't take pride in any achievements that followed your cheating. You might as well play a normal campaign and reload.
The grown up thing is to accept failure when it comes, forge a plan B and recover the situation. Now that's achievement and it's also good for your character. It also teaches you to be less reckless and manage risks by having backup plans in the future.
The game is only required to plug exploits in the game itself, not have complex anti-cheat systems because you are a poor loser.