hun, I've done it. I've put DD1 in her cot and went and stood outside.... waited 5 minutes and went back. I felt horrible afterwards, but I needed to walk away to stay sane and not throw her.

ETA: with DD2 I found having a bath or shower together helped everything. With DD1 if it was raining I put a rope in the loungeroom and pushed the pram in circles going over it with loud music on headphones...