I have been married to my long lost "one who got away" for two years now after years of being apart. We are both approaching 40 now, to give it perspective. Well, while she got away, she had a baby with the biggest mistake of her life. Yay. When she divorced him, we were free to talk to each other again as friends. He forbid it. So we did, things were fine. We went out and ate (alone), we spent time together (alone). It got more serious and I met SD (now 10, then 7). My first impression was that she was very well spoken for 7. She seemed confused at my presence and I was introduced as a "friend". We went to the lake and I played in the water with her. My now wife's mother tagged along, as that was normal for them... the three of them doing things together like family all themselves. Now, seeing as we had a history, there wasn't the "how many brothers do you have?" and "what's your favorite color" type dates. We already were best friends. Just best friends who were forbidden to talk to each other while she was married to that asshat.
Here is the part where you are asking, "why did she marry him and not you then?" - because I'm a female and that mother who goes everywhere with them is SUPER Baptist. My now wife just couldn't bring herself to break her Jesus loving mother's heart, so she married the first man to ask. She just got to the age of "I got one life, wtf am I doing wasting it like this?".
Originally, SD was in public school. My wife works weekends and would get "on call" at least once a month before we got married. That gave us at least one night to ourselves while SD was with her dad, and the days while she was in school to do stuff - errands, chores, daytime nookie even. NOW, however, SD is homeschooled. I. HATE. IT. I hate it so bad. AND my wife rarely ever gets "on call" from work, so her days on are our childfree days. Ok, right, so now you have a picture...
My SD has complete meltdowns over work, so there is one of those just about daily. They take up hours of time, she cries, she hits herself (yes she is seeing a therapist), she screams and breaks things. All because math is hard. And, no, we don't have her advanced for her age... she is actually behind, which is why she is in homeschool. My wife goes from ignoring these rants to cuddling and talking about what is bothering SD. Starts at 7am and goes to 10pm... and I am the jerk for wanting this over and saying this isn't working. My wife gets tired of it and will then just take SD to the zoo or to the park or something "to learn" there... but it just is a trip out to keep SD from pitching a fit.
Friday comes, my wife takes SD to her dad or her parents depending on if BD is actually going to get her or not. She goes to work, I have weekends off generally. I do yard and housework that got ignored all week. Sunday night comes, I pick up SD from wife's parents (they make contact with BD, I can't stomach him for his past abuses). Monday my wife sleeps a bit (nightshifter) and then we are off with the school work and meltdowns.
I am in college. My wife is so good for me. She pushes me to be the best I can be and when I want to give up, she brings me back. So I am well aware that SHE is perfect for me. Always have been. I just can't deal with the dynamic here anymore.
We have a week in the summer that is just ours. I find I live for it. This summer SD has been gone for it's entirety... which is not the norm (and no, they don't follow their parenting plan). SD is allowed to decide. She has been choosing her BD this summer because he remarried someone with kids her age. Summer has been great and I realized that all the tiny fights and the tension in the house is absolutely not there with SD gone. It is obviously SD being here that causes our life so much stress. Yet, I'm blamed for it when she is here. I am told "I just don't like her" and "she feels your hate".... I DO NOT HATE HER. I hate her fits. I feel like she could benefit from some sort of discipline, any... just try something. I hate the way these two parent her. I hate that I have to live with the result of their crappy parenting. But I don't hate her.

So what to do? I do not want a divorce. Never. I lived without her before and it was hell. She is the one you never get over. So should I just take myself out of the house more? How sad is that? I want to date my wife, not myself. Yes, we have had these talks. Yes, she says we need to date and it's important... but we never really do until summer when SD can go to her BD on weekdays when my wife is off work. Then I have to be off work to make it happen too. Am I being whiney? Is it normal to only get one week a year with a spouse? If so... why marry?!?!