Welcome Rachael
Here is definitely a place you can come vent and even brag - perhaps you have noticed there is a whole thread devoted to bragging since so many people here don't have a safe place to do this.
It sounds like you have a wonderful little girl. And when you are with the other moms maybe you can talk about things like how much she loves (or tortures) that cat or other topics that do not include milestones. Then come vent or brag away on here about the rest. :-)
I have to say this is the most welcome I have ever felt since becoming a parent! I've read the brag threads and love everything all the kiddos are up to! Some of them I can relate to, some I get a lovely picture of what's still to come!
I'll definitely heed your advice about topics with other moms. I'm learning slowly but surely what NOT to say to anyone who isn't in the same boat! Thanks to all of you for being so supportive! I'll look forward to hearing about all your children as well.