OP's situation is more complex because of the child. We all know kids that grow up without father tend to have more often various issues in later life (I've seen folks like that everyday in pre-covid times, it becomes glaringly obvious once you know what to look for in their behavior).
But then also staying in cold detached relationship ain't the best for the child either - they are very perceptive and seeing everyday cold parents relationship affects them negatively too. There isn't a nice, quick and easy solution for everybody without some real chance of harm for the most vulnerable - that's why it often becomes one's low point of life. You know its bad for the person you love the most, and you don't have a clear win scenario. Amicable split with good care from both sides is probably best, but unfortunately rarely seen.
Fuck I wish we were taught more these kind of things in schools (selection of life partner is tricky, test the relationship and each other hard before having children, but also things like effective communication, teamwork, how to generally thrive in system - ie taxes, how to setup a 1-man company etc.). Imagine nation of people raised like that, instead of memorizing tons of stuff that was forgotten very quickly but spent a lot of time/energy on.
There are many, not 100% for this reason, but often are - unhealthy competitiveness, inability to be happy with what one currently has (clue - it won't get much better once more is achieved). Children from broken families often don't believe in long term relationships or starting family and come up with reasoning like overpopulation and actually doing good for mankind. General insecurities. Afraid of generally any commitment. Emotional intelligence on a low level.
There are more extreme cases - wife works currently as doctor in prison, and most folks there didn't have a good (or any) fatherly model. Women have their own 'daddy issues' side to it, but most above applies too (experienced first hand in one relationship, it was pure nightmare although she was smart and professionally successful).
I grew up with loving parents and siblings, we're still a strong coherent family unit.
Unhealthy competitiveness, inability to be happy with what one currently has, don't believe in ... starting [a] family, these things all apply to me.
My parents will celebrate their 50th wedding anniversary next year. I distinctly recall my mother describing my father as her best friend about a decade ago when on the phone to one of her friends.
Suffice to say, I disagree with your theory of tell tale signs. You've just put people in a box incorrectly.
Is this also different between growing up without a father vs growing up without a mother? I have some thoughts on this of my own, not sure how accurate they are.
I suspect the first case causes more competitiveness issues, general aggressiveness (or toxic masculinity if you will, though the term is somewhat problematic) The latter more issues with trusting women, intimacy, etc. Not believing in long term relationships might be more likely if one of the parents is completely out of the picture, not so much gender related. This is from a male perspective, perhaps from a female perspective the two cases can simply be flipped.
There probably is some research into these things, but I wouldn't know where to start.
Absolutely none. Kids who grow in families with issues have higher rates of issues. (And kid having issues tend to break family too).
But it is not glaringly obvious at all who grew up with missing dad (or missing mom). None of the issues the sibling mention are exclusive to such people nor so much more likely to be found in such people.
It's funny how the exact problems you were unprepared to face in life are what you think should be taught in schools to the exclusions of other things.
Once you have child, you are forever tied together through child. If they divorce, he wont be with child every day. He will be with child either on alternating weeks or every other weekend or whatever custody they agree on.
And he will still have to cooperate with ex. (Through here it sounds like fairly doable.)
But then also staying in cold detached relationship ain't the best for the child either - they are very perceptive and seeing everyday cold parents relationship affects them negatively too. There isn't a nice, quick and easy solution for everybody without some real chance of harm for the most vulnerable - that's why it often becomes one's low point of life. You know its bad for the person you love the most, and you don't have a clear win scenario. Amicable split with good care from both sides is probably best, but unfortunately rarely seen.
Fuck I wish we were taught more these kind of things in schools (selection of life partner is tricky, test the relationship and each other hard before having children, but also things like effective communication, teamwork, how to generally thrive in system - ie taxes, how to setup a 1-man company etc.). Imagine nation of people raised like that, instead of memorizing tons of stuff that was forgotten very quickly but spent a lot of time/energy on.