First off, single parents do a good job raising their children most of the time either sex parent.
A child needs ideally both parents to get the right signals, on how a woman behaves with a man and the other way round, that said, a child in a single parent family will get those signals from male role models in his life, uncles, male friends of the family, even parents of his friends, and male daycare workers (cannot think of the politically correct name for them) even I suppose from TV (sometimes) so unless the parent has nothing to do with men then he will be able to pick it up.
that actual term you use is a little vague "masculinity" do you mean the whole package in being masculine/male or just the Bruce Willis rough tough idea.
RR