I know how frustrating that can be. I'm in the same boat right now, and had a huge vent yesterday on the naps forum. But, the best we can do is ride it out. I know its a phase, and it too shall pass, but I also know how hard it can be, in terms of patience. If its getting too much, I just take a minute to take a deep long breath, and keep doing what I am doing (laying her down). Hopefully, she'll get the hang of it soon enough.
Hang in there.
Sumita