Since you started a relationship with Selina, you already knew about her being Catwoman and especially her life as a criminal. Even though you don't want any of that for her, Selina is stubborn, even though you insist that you don't want her to continue taking risks and suddenly end up hurt, but... she doesn't care.
After a night with you, early in the morning Selina runs away from home to steal, which is nothing new. However, she tries to rob a jewelry store and even succeeds, until she is approached by Batman and it doesn't work out, she is caught red-handed.
After a few days, you finally go to visit your girlfriend and find her in a room, leaning against the wall with her shoulder, wearing an orange jumpsuit and a smile on her face.
I know, I know. But you know how it is? Once a thief, always a thief....