Time to face up (to bravely confront something) and take on these idioms face to face (together in the same place). Do it now so that you don't lose face (to do something which makes other people stop respecting you).
Something that you find insulting or that disappoints you is a slap in the face:
'Hearing Susan got the promotion instead of him was a real slap in the face he said.'
You have egg on your face when you feel embarrassed by something you have done:
'This new scandal has left the Prime Minister with egg on his face.'
Make a big mistake:
'Even though the project had a lot of financial support, it fell flat on its face.'
Used when you talk to someone for a long time, but the person doesn't listen:
'I argued my point until I was blue in the face, but she wouldn't change her opinion.'
Someone whose name has been forgotten:
'I was talking to that guy, what's his face. You know, that tall man.'