If your boyfriend's most recent hukou was before marriage, then the marital status is "unmarried"; if you haven't applied for a new hukou after marriage (up to the time of the divorce), then it's "married". This marital status is very slow to be updated.
But the ID card also contains a lot of other information, such as where you've traveled by car or plane, what hotels you've stayed in, whether you've been criminally tainted, and so on.
As for your question about whether you can find out marital status, I think you can still be lucky and not worry too much. I'm not sure if I'm going to be able to do that. I'm sure you'll be able to find out if it's possible to find out if you're married or not.
Reading your additions, you should not be able to find out married information, let alone divorced.