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Something is up with you. And for the first time I am actually concerned.
And to be honest with you, me too. I think I am broke.
Anything can be fixed though. Remember that.
Your modesty and overall hope boat has sunk.
As your doctor-
Ha!
as I was saying, what do you think the "tipping point" in any marriage is? Is it love? Sex? Attraction? Commonality?
How should I know? I got married at 23, spent 11 years doubting myself and my decision making ability, and had a child under fucked up circumstances that have unloaded piles of guilt on me that no man or father should have to endure. I have tried to support my wife who has more emotional problems than a maternity ward at feeding time. I have begged mercy with both my wife and the God I struggle to follow. I have separated myself from my family, regardless of how shitty they are, to earn her trust and love and I have stepped to the edge of reason, and plummeted foolishly over it. What is my tipping point...Doctor?
Let me ask another question then. What do you want in your life right now. And don't hold back, not here, not with me. Get it out there so we can then skimmer through the goo and find the nuggets that hold value. 
I want the woman I married. I want the young, full of life, woman who gave up everything to pursue, what she thought to be at the time, true love, risking everything she fought, kicked and clawed her way to have back home. I want the woman who wanted me, everything single inch of me, the moment we stepped out of the airport. I want the woman who I could not wait to come home to from work, to hold, or kiss, or just sit next to and watch mindless television for hours. Yes, she had high expectations then, but she also carried herself along happily, even if it was a facade, as though the only thing that mattered was us. Us versus all the rest. Did I squander it? Yes, I made plenty of fumbles along the goal line, but goddamn it I have more than made up for them. I want the woman who loved, even if she was faking it. I want to know this fight is for a reason that is not revolving around another girl about four feet tall.
So the majority of your misery centers with your wife.
Always has been, hasn't it?
What if you left her? Aside from the shit your daughter would have to put up with, and the unfair disadvantage it would be to her. 
That is the complex part. The easy part is I would be forever broken inside. K has become a part of me, and I would like to believe that I her. But the chemistry no longer feels like lovers. It feels like long time friends torn asunder by some silly ass disagreement, or jealousy for the girl each want but cannot have. The ONLY thing we share now is our daughter. I am not sure if its a matter of one given up or not, but that is the cold hard fact. Our love is baseless as individuals, but blossoms as parents.
Ah. The complex part. 
K has fallen down a rabbit hole of self-doubt and insecurity unlike anything I ever known. She refuses to get help or allow me to help her. She refuses any medication that could possibly help her focus and the worse part about it all is that final piece of our family, a second child, looms over like a prized championship just out of reach. The missing link to our family happiness. I can't talk to her about it. I can't mention it. And if I try, she turns on me and attacks viciously at times.
So, reach out to her again. But do so carefully. Speak to her indirectly, and, if she is listening, maybe you will not have to beg anymore. 
And if she ignores it, then what?
Then you become another statistic, my friend. 
And how do I get to her?
Same way you have always expressed yourself. 

(A)men. 

It's worth a shot. What more do I have left?