When Babies Cry...

Is there anyone on this earth who enjoys listening to a baby cry? I'm not talking about enjoying the feeling of being able to comfort your crying baby or hearing them cry for the first time after you bring them into the world. I'm talking about when you have to put your baby to sleep for a nap or bedtime or even just have to put the baby down for any reason. I know that it has to be done, and that babies have to cry but honestly, it kills me to sit her and listen to my baby cry. I've done all I could to comfort her though. I changed her, fed her, rocked her, even sang to her and read her favorite story. Now its up to her right? Am I a horrible mommy for laying my angel in her crib and letting her calm herself down? I feel terrible considering all that she has on her plate right now, but she's exhausted and you can see in her eyes that she needs a nap?

I feel like this is a constant battle for me. The doctor has told us that its healthy for her, and that she'll eventually drift off to sleep. but it breaks my heart. the normal routine has been, rock/feed, sing, lay down, cry, sleep 20 min, cry 10, sleep 25, cry 5, sleep 10, cry 5, sleep 45. then what? when she wakes up crying, do i pick her up?  do i let her cry for 10 minutes and see if she really is done with her nap?

All that I know is she sleeps perfectly well at night, and usually falls to sleep in 5-10 minutes or so, but nap times are a different breed altogether.