why is a man's choice to not take responsibility for his child not protected by the same reasoning? Why is it not a choice "central to personal dignity and autonomy" under the rubric provided by the court?
The somewhat flip answer is "because its just money."
A more detailed answer is, the duty to pay child support is just not a liberty interest of the sort refered to. Not all (and in fact not many) things "related to procreation" are protected by the Constituation. Sex (and until just one year aog, only heterosexual sex), contraception, abortion - that's it. I think it is not a stretch to look at those things - all of which involve very intimate, personal acts is a far cry from writing a check each month. Just because that check is being written
because of procreation, does not make the act of writing a check some highly person, private act due the protections of constiutional liberty.
Child rearing is not protected, or at least not fully. You do not have, for example, a constitutional right to violently discipline your children. Same with education. Every state requires that children below a certain age must attend school. Now, the parents have (guaranteed by the constitution) broad discretion on how their children are to be educated, but no choice as to whether they will be educated and there are limits to this guarantee even within legitimate educational choices.
It should be really clear that there is no protection for things "related to marriage." The individual States have always defined for themselves what marriage is and even are given leave to refuse to recognize marriages of other States. I am confident that if a State chose to do so, it could choose to not recognize marriage at all.
I could really go on an on about all the things "related to marriage, procreation, contraception, family relationships, child rearing, and education" that are not protected at all. But basically, if its not sex, contraception or abortion, it has no constitutional protection.
While the SC often draws some seemly arbitrary lines while devloping constitutional doctrine, I think in this case the line is not at all arbitrary. Looking at sex, contraception and abortion, I think you can see the clearly deeply personal, private nature of those acts that make protection of them necessary, and likewise, can see that the right "not to write a check" is equally obviously not something "central to personal dignity and autonomy."