did liesel and max get married?

This is up for speculation. Liesel does get married but the man's identity is not mentioned. Zusak has commented on marriage between Liesel and Max in a Facebook post,

Still, like I said, for me (and it is only my opinion), Max and Liesel DO stay together, but not necessarily in the way some people think…But of course, I’m still more than happy for readers to believe they do get married and live their lives together. At the end of the day, it’s still up to you, and that’s the beauty of books. In so many ways, they never really end.