Am I the Only Bad Mom in the Room?

When is the last time someone was describing a root canal and it's excruciating pain to you, when they stopped in mid-sentence and said, "oh, but it's so great'!?
That is what it is like to try to have a candid conversation with a mom. They start talking about tantrums or bossiness that is driving them to exhaustion and then they stop and say "Oh, but it is so great"! Just when we are getting to a point of really sharing about the challenges of child rearing, they derail it with a comment like that. It is as if they aren't allowed to have other feelings about motherhood than the eternal bliss that goes hand in hand with three year olds' tantrums.
Give me a break, it is challenging, yes it is rewarding, but how are you ever going to get through all of this if you are in denial? Okay, when you push them through the birth canal, you are making a lifelong commitment to love them, but still...you bring your own stuff to the equation. It's okay to occasionally be irritated or disappointed. It's as if somehow saying that it is challenging, you are negating the child.
I attribute it to the thinking mom, attachment parenting model, where we are trying to undo our parent's damage. Somehow you are supposed to be supermom who overrides all of these mixed feelings about parenting. To be fair, upon reflection, they are really great, but that is something to tell them, not another parent who is struggling with parenting and wants to have a heart to heart. whatever happened to the village that was going to help me raise my child, did they all somehow move into the exurbs and leave me alone to parent with all of its' challenges?