IMHO, the answer boils down to difference between beginner's and advanced practitioner's attitude.
In beginner's mind, there is a strong conflict between Samsara of day-to-day life, and the peace of Nirvana. Buddhist practice is seen as a mean of cutting the fetters that keep reengaging one in the endless cycle of Samsara with its pointless activities and endless frustration. The challenges of day-to-day life are taken as nuisances or obstacles distracting one from study and practice.
In an advanced practitioner's mind though, Samsara is seen as an inverse projection of attachments, and Nirvana is understood as a fully integrated experience free from conflict between desirable and undesirable, not a place apart of Samsara. For such practitioner, all activity becomes dharmic practice, with glimpses of Nirvana hiding in the here and now, behind the curtain of dualistic mind.
As someone who's been married for ~19 years, and a practicing Buddhist for about the same time, I can say that married life provides endless possibilities for overcoming one's pathological habits, dropping one's hang-ups, surrendering one's egoistic facades, and sacrificing one's petty personal goals in the name of the higher good. As long as one operates in the right context, basically that growth requires overcoming the ego, married life becomes the best dharma school one could ask for.
As far as actual parenting (my son Matthew is going to be 16 in March), there is nothing as satisfying as helping another sentient being emerge less caught up in illusions than you were.
Finally, when we speak of attachments in (Mahayana) Buddhism we don't mean commitments or responsibilities. We mean attachments to preconceptions, prejudices, to (illusory) certainties, to self-image, irrational attachments to unrealistic expectations, all kinds of obsessions etc. In this context the answer to "How can you raise a child without being attached?" becomes very obvious -- the less attached you are, the better you do as parent.