Sometimes you screw up so bad that the person you hurt doesn't want to be around you, but they don't want you completely out of their life either. So you end up "in the dog house"--that is, resentfully ignored. Here are some steps you can take to get out of it.
Steps
Swallow your pride and apologize.Really apologize. That means understand what you did wrong, why it was wrong, take full responsibility for it (no excuses, no explanations, no "I'm sorry but"), and make amends.
If you're getting the silent treatment and you're not sure why, confront them. Sometimes people get upset and they don't know how to express their dissatisfaction except to avoid interacting with you. Other times, they think you should know by now what you have done to upset them, so it requires no explanation. Either way, the sooner you can talk about it, the sooner it can be water under the bridge.
Make silent peace offerings. Wash the dishes or do the laundry without being asked. Buy them a flower and leave it next to their alarm clock or coffee maker. Fold a dollar note into a heart and put it in their pocket.
Be comically sweet and apologetic. Do things that are shamelessly humble, so the person who's mad at you won't be able to resist laughing. How about serenading her when she comes downstairs in the morning? Or writing "I'm sorry" with frozen hot dogs across his car dashboard? The fact is, if someone cares for you, they can only stay mad at you for so long, and humor is a great way to disarm them.
Let things slide back to normal. While the person might appreciate your efforts, they shouldn't stay angry and expect you to jump through hoops forever. Some people, however, enjoy the power that being angry with someone brings. If you're in the dog house a lot, you might be in an unhealthy relationship. See How to Recognize a Manipulative or Controlling Relationship.