Da or di
In the following sentences:
Sono pazzo / pazza di te.
Sono abbagliato da te.
What factor causes the use of di or da?
In "Sono abbagliato da te", "da" translates to "by" (I'm blinded by you), because it's a passive sentence: the active form would be "tu mi abbagli". "Da" is always used when identifying the actor in a passive sentence, just like "by" (e.g. it was made by me).
In "Sono pazzo di te", the usage of "di" is rather idiomatic. It could have been "impazzisco per te" too.