Are you part of the FReeper family table discussion group on Fridays? You have a great question about raising boys and someone there may help.
Let me tell you though. I have a nephew who came to live with myself, his mom and my mom and my dad when he was three. My dad died four months later. He was totally surrounded by women for the majority of his life. He now has a wife and three boys. He works two jobs so she can homeschool. He attributes that work ethic to the strong women around him and his Grandpa's memory that stuck with him.
Your husband may not be around as much as you would like, but a father being in the picture is the best thing that could happen to a child. (even a Grandpa can be a great dad)
My son knows why dad is not around much. My husband lost his job last December, and started a new one in January. I've been the one explaining that it is much better to have Dad working hard than to not have a job at all. We continually say prayers of thanks that Dad has a job.
My husband also takes my son with him as much as possible when he has to run errands on the weekend. We also let my son stay up late during the summer so that he has some time with Dad.
I guess that is one of the biggest lessons my son will ever learn: to work hard so that there is a mom at home to take care of the kids.