On the one hand, I have no idea what Ashley Judd saw in that kid. On the other hand, that kid turned out to be a near-omnipotent being, so I guess that was her loss.
"Space madness" in this case was just some nebula or something that basically turned the air or something into alcohol. I can't remember Crusher's exact explination, but simply put everyone was made super drunk by an anomaly.
Which makes the fact that Data was affected by it hella weird.
What's worse is that this is all the explanation we get for why Data was affected and it comes from Data himself while he's affected...
We are more alike than unlike, my dear Captain. I have pores. Humans have pores. I have fingerprints. Humans have fingerprints. My chemical nutrients are like your blood. If you prick me, do I not leak?
So apparently, androids can get drunk because they have pores, fingerprints and chemical nutrients.