The Messy House Phenomenon

If life is about learning lessons, and that you will keep getting the same lesson over and over until you learn it, I have mine!
Why is it, that certain types of people only seem to turn up, when the house is a wreck, you're screaming at the kids to stop breaking plates as "Science Experiments" The dog has diarrhoea, the baby literally wont stop crying, the dishes are piled and you were too busy to put on deodorant, let alone brush your hair?
Why did they not show up literally 12 hours prior when the kids were hugging and one was sleeping, you had make up on, and the place was spotless?  Why is it always the one person who shows up in your hour of chaos, who is the one person you seem to be desperate for their approval?
And why is the one person you are desperate for approval from, a nasty person you want to be nothing like? Seriously, this MUST just be me. This must be a lesson.
I have this neighbour....... She looks like a troll.  I'm not kidding.  I'm not jealous of her, and would hate her life..... and for some reason I am desperate for her approval.  Not outwardly, it takes a lot of soul searching to pull this out of yourself, that she makes me so upset, because for some reason I must be desperate for her approval?
Why? 
This woman has no children, and for some unknown reason has to tell me about her happy decision not to procreate.  Not just, "Yea, we chose not to have kids."  But a continual "Your life is my nightmare."  Why does this bug me so bad?  Do I really care what Troll lady says?  I don't want her life, I would hate it actually.  Why do I care??????
There must be some life lesson here.  She is the only one who happens to ring the bell, just when Chaos 2013 just happens to be unfolding in my home.  It just happens to be her, who comes around at the very moment of the day I don't wish others to appear.  It seems I need to prove myself happy to her.  That she messed up in some way, and she is confused what happiness looks like.
Maybe she is trying to prove her level of happiness to justify her decisions?  Why are we even competing?
I get not having kids!  How fun is all that disposable income!?  How did you sleep last night?  How good is your weekend at the winery?!  That's awesome and I get it.  I don't look down on people who chose not to parent.  Good on you!  Why does it hurt so much that she choses to look down on my decision?
I feel like we can't see in people., what we don't possess in ourselves.  This means, you and I can't get murdering someone.  We can't see liars and cheaters, because we don't lie and cheat.  People can blind side us, because we don't see that.  What we DO see in others is their nastiness.  We see nit picky little issues when people are selfish, or mean.  The reality is those traits are in us.  You don't want to admit it but they are.
I remember one day in a class, this woman wouldn't shut the fuck up.  She was dominating the conversation, and complaining.  I went crying to my friend "She is so selfish, and making such a pity party! I needed to talk! "  Her response was "What are you doing right now?"..................shit.
So I am working through, why Troll lady bugs me.  This reoccurring lesson I am not learning.  That I feel the need to prove my decisions and to prove my happiness. Prove I have a clean perfect home, perfect happy kids, an adoring husband and no stretch marks.  Well that's a load of shit!  I know I'm happy, but if she only irritates me because she is a reflection of me....... I think this means I am trying too hard to prove myself to others.
I should probably stop that.  I like me, but I do feel out of place at times.  I don't look or act the part I am in, and that bothers me. I feel I have to prove that I am worthy of this life, and that I am proud of my decisions.
Reality is, this life is hard, yet amazing, terrible and joyful, sleepless and fulfilling.  I can't let others opinions dominate my existence. 
But my good God would it be nice for her to ring at just the moment of peaceful, blissful, happy children, adoring husband, dishes done, hair straight, make up on, 40 minutes a day of my real life. Wishful thinking!